The Internet offers a wealth of excellent tools, information, and entertainment, and it asks very little from us in return. So don't get upset when a poorly designed online tool or site gets on your nerves. Instead, use Greasemonkey, a free Firefox addon that harnesses the power of JavaScript to right usability wrongs and improve the functionality of specific websites and of the Internet at large.

Greasemonkey can improve just about anything it touches, whether by adding must have features to Gmail, streamlining your social life in Facebook, or speeding up your blog posts. The best part? Thousands of Greasemonkey scripts are free to download, and installing them is as simple as clicking a single link.

In my day job as senior editor of Lifehacker, I regularly use Greasemonkey scripts to streamline my online workload, stay organised and speed through the web.

Even though Greasemonkey scripts are written primarily for use in Firefox with the Greasemonkey extension, many of them also work with Internet Explorer (via IE7Pro or Trixie), Safari (try GreaseKit or Creammonkey), and Opera (which includes built-in support for the scripts). After installing the appropriate add-on for your browser, you're ready to improve your web experience.

Multimedia Tools

Pump up your favorite online music, video, and photo sites with these smart scripts.

1. Inline Google MP3 Player

Inline Google Player; click for enlarged image.When you stumble upon a link to an music file on a web page, the dance is generally the same: You download the file and listen to it with your desktop music player, or you click on the link and listen to it in your browser with its default player plugin. Either way it disrupts the flow of your browsing experience.

But the Inline Google MP3 Player script gets you back in the flow, automatically detecting linked MP3s and embedding Google's Flash player on the page so you can play the file inline and hassle-free.

2. Videoembed

Videoembed; click for enlarged image.Since video sites like YouTube don't offer much useful content beyond the actual video (that's right, I'm disparaging YouTube comments en masse), there's no point in going to YouTube to watch a video when you could embed it directly in the page you're looking at.

That's the idea behind Videoembed, a script that automatically embeds videos from sites like YouTube, Google Video, and Metacafe whenever a site links to a video without embedding it. Now instead of clicking through to YouTube, you can watch the video directly on the site that linked to it.

3. Greased Lightbox

Greased Lightbox; click for enlarged image.You know the drill: You're doing a Google Image search, but rather than give you direct access to the pictures you want to see, Google makes you click through a couple of links to get to the full-size image.

The Greased Lightbox script turns your Google Image search results, along with gallery pages on sites like Flickr, Facebook, and MySpace, into inline, AJAX-driven galleries that you can navigate from your keyboard. Not only is it faster, but it has a more attractive interface than do most other photo galleries on the web.

4. Flickr Camera Images

Flickr Camera Image; click for enlarged image.If you spend much time surfing the popular and addictive photo sharing site Flickr, you're bound to catch the shutter bug. You may also find yourself wondering, "What camera took that photo?" To read about the camera used, click the 'More properties' link, and if you install the Flickr Camera Images Greasemonkey script, you'll also see a photo of the camera in question. If you decide that a particular camera's output is so great that you simply have to have it, click the image to jump directly to the camera's listing on Amazon.

Online Time Savers

These handy Greasemonkey scripts help keep online time sinks under control.

5. NoDelay

Anyone who has downloaded files from sharing services like RapidShare or Megaupload has run into download landing pages that require visitors to wait for up to 2 minutes before they can download the file they came for. The NoDelay Greasemonkey script takes you straight to your download, with no unnecessary pauses or other tiresome hoop-jumping required.

6. Stealth Kiwi

Stealth Kiwi; click for enlarged image.The Internet is a magical place. So magical, in fact, that unless you have the self control of a Zen monk, you can easily waste hours every week browsing various guilty pleasures online. The Stealth Kiwi script keeps a tighter rein on your unproductive surfing habits by preventing unfettered access to your browsing weaknesses during your 9-to-5 hours.

To help you preserve your sanity, however, Stealth Kiwi permits you a 10-minute browsing break every hour. This completely customisable script is the closest thing I've seen to bottled self control.

7. The Movie Dude

The Movie Dude; click for enlarged image.Movie lovers tend to spend hours researching films on the Internet Movie Datebase, reading reviews on Rotten Tomatoes, and adding films to their Netflix or Blockbuster queues. The Movie Dude script adds links between these popular movie destinations (and others), bringing greater continuity to the process of finding a movie you're interested in on IMDb, researching it at review sites, and adding it to your queue or purchasing it online.

Gmail Enhancements

Overclock Gmail and boost your productivity with these essential scripts.

8. Gmail Addons

Gmail Addons; click for enlarged image.If you've ditched your desktop email applications (Microsoft Outlook and the like) but you miss being able to manage your email and agenda through a single window command center, you need the Gmail Addons user script.

By default, the script embeds Google Calendar inside Gmail so you can access both from the same place, but it can also embed Google Reader, the popular Remember the Milk to do list application and other great productivity web apps via additional scripts designed specifically to enhance the functionality of Gmail Addons.

9. Gmail Macros

Gmail is easily the best web-based email application on the planet, so you might be surprised to learn that a Greasemonkey script called Gmail Macros drastically changes Gmail for the better. Created by a Google employee (though not as an official Google project), Gmail Macros enhances Gmail's already robust set of keyboard shortcuts, so you can navigate your inbox and label your email messages on the fly, without taking your hands off the keyboard. Better yet, it accomplishes all of this through an easy to use graphical interface that takes the guesswork out of remembering the keyboard shortcuts.

10. Gmail Attachment Icons

Gmail Attachment Icons; click for enlarged image.With nearly 7GB of storage space, and counting, available, you probably share more file attachments through email than ever before. At its default settings, Gmail indicates email attachments with a generic paperclip icon and provides no hint as to the type of file attached. The Gmail Attachment Icons script embeds small icons in place of the generic catch all to indicate whether the attachment is a picture, a Word document, a PDF, an MP3 or a zip file.

Web Editing and Blogging

Here are two superb scripts that no power blogger should be without.

11. Textarea Backup

Textarea Resize; click for enlarged image.You've just finished writing the ultimate blogger's opus, but before you have the chance to hit Submit, your browser crashes and you're back at square one, except this time you don't have the original exhilirating rush of inspiration.

Had you installed the Textarea Backup user script before this catastrophe struck, your masterpiece would have been saved after every new keystroke. It doesn't matter whether your browser crashes or you accidentally close the window before submitting the contents of the text area, everything will be restored to the text field automatically the next time you open the page.

Note: Textarea Backup may cause problems in Gmail because it tends to save the last address you sent to, quietly filling in the cc and bcc fields with that address. You can avoid this problem when using the script by adding mail.google.com to your list of excluded sites.  

12. Textarea Drag Resize

When you have a lot to say but the comment text field on your favorite blog accommodates only a few lines of text without scrollbar intervention, the experience is like trying to pour the ocean into a tea cup. The Textarea Drag Resize Greasemonkey script adds a small resize icon to the corner of every text area on the web. By clicking the icon, you can easily extend the associated field to dimensions that befit your verbosity.

Social Networking

Use these smart social site scripts to make your friends' online profiles less annoying.

13. Facebook Profile Cleaner

Facebook used to be the clean, simple alternative to MySpace and its practically seizure inducing clutter. Then came Facebook applications. For some Facebookies, these applications are the social networking site's greatest innovation. For others, nothing is more irritating than a page littered with SuperPokes and ersatz Scrabble boards. The Facebook Profile Cleaner script removes all custom apps and (optionally) other specific Facebook features you dislike, from the profile pages you look at.

14. MySpace Custom Style Remover

Despite its recent redesign, MySpace remains one of the most heavily trafficked sites on the Internet, and one of the messiest. One source of MySpace's appeal is that users can customise the look and feel of their profile page to fit their personality. The problem is that many of your MySpace pals probably have pages that, fairly or not, represent their personalities as loud, ugly, and ridiculous. The MySpace Custom Style Remover returns all MySpace profiles to their clean, default origins.

Content Filtering

Here are two great scripts to help you shield, or unshield, your eyes from online filth, and one to take the mystery out of TinyURL addresses.

15. Profanity Filter

The web's openness and impression of anonymity have redefined freedom of speech, but one side effect is that profanity has become ubiquitous online. The Profanity Filter script censors all of that awful Internet ***, replacing common expletives with three harmless asterisks. This script's default list of filtered words is large, but you can easily edit it to add words that you object to or to remove words that you don't find offensive. So if you never want to see the word "platypus" again, you don't have to.

16. Uncensor the Internet

On the other hand, you're not an idiot, and at sites that censor words with just a couple of figleaflike asterisks, such as "bull**it" or "platy**s", you'd have to be pretty dim not to recognise what's being obscured. If that kind of ineffectual fastidiousness rubs you the wrong way, you can use the Uncensor the Internet script to restore partially censored words to unexpurgated form for maximum shock value.

17. Tin Foil Hat

Tin Foil Hat; click for enlarged image.URL shortening service TinyURL is the de facto tool of choice for shrinking long web addresses to ensure that they won't break in an email window or take up too much space online. Unfortunately, the magically truncated URLs also provide no context with regard to where the link will take you. If you're as paranoid as I am, that kind of ambiguity can eat you alive. But after installing the Tin Foil Hat script, you can hover your mouse over any TinyURL link to reveal the actual destination of the TinyURL address. Never again will you be forced to click blindly through.