Windows Spy Keylogger is a simple free tool for recording everything typed on a PC.
Installation is more complicated than we expected. First, you download an archive. Unzipping that produces a password-protected archive and a password.txt file. Open the text file, read the password, use that to unzip the archive, and you get another executable, which then downloads the actual program and installs it for you (phew).
Fortunately, everything else is very straightforward. Launch the program and you can start or stop keylogging with a click; there's a Settings option to start logging automatically when Windows starts, and everything typed is saved to a text file (C:\Users\[UserName]\AppData\Local\Temp by default, though this can be whatever you like).
Another technical plus is the program doesn't have to be run as an administrator. It works just as well when run as a standard user, recording both 32 and 64-bit applications. (If it doesn't work for you immediately after installation, reboot and try again.)
The package isn't exactly stealthy. Anyone who checks Control Panel's "Programs and Features" applet will find it listed as "WindowsSpyKeylogger", and there's a "Windows System Logger" process visible in Task Manager, so even non-technical users will probably spot it eventually.
Still, Windows Spy Keylogger might be useful for monitoring what young children are doing on your PC. And it could help you test security software which claims to detect keyloggers, or stop them from intercepting your keypresses.
Windows Spy Keylogger will be easily detected by most users, but could help you monitor young children, and might be handy for testing other security software.