Oracle VM VirtualBox is an industrial-strength open source virtualisation tool that makes it easy to create virtual machines (VMs), simulated computers that run on your PC but act as though they were separate systems. It's a powerful capability that has many different applications.
If you'd like a closer look at Windows 8 before you upgrade, for instance, then you could install Microsoft's latest in a VM, then access it in a window on your XP or Vista desktop.
Or maybe you've upgraded to Windows 8 and find a favourite old app doesn't work any more? Create a Windows XP VM and you might be able to run it again.
VirtualBox can also be a useful security tool: if you download and test apps in a VM, then any malware you might encounter will be isolated from your main system.
And it's the perfect choice if you want to try out another operating system with the minimum of hassle. Right now you can install Google Chrome OS, all the mainstream Linux variants (2.4 and 2.6), OpenBSD, OS/2, ReactOS, SkyOS, DOS, and just about every version of Windows there's ever been. (Of course you'll need to have the system discs to hand.)
What's new in version 5.0:
- Paravirtualization support for Windows and Linux guests to improve time-keeping accuracy and performance
- Make more instruction set extensions available to the guest when running with hardware-assisted virtualization and nested paging. Among others this includes: SSE 4.1, SSE4.2, AES-NI, POPCNT, RDRAND and RDSEED
- xHCI Controller to support USB 3 devices (requires the Extension Pack)
- Drag and drop support (bidirectional) for Windows, Linux and Solaris guests
- Disk image encryption (requires the Extension Pack)
- GUI: Detach mode: Terminate the GUI but keep the VM running and re-attach to a running VM process (see here).
- GUI: VM guest-content scaling support (including 3D acceleration)
- GUI: New User Interface settings page for customizing status-bar, menu-bar and guest-content scaling
- GUI: New Encryption settings tab for customizing encryption options for disk images
- GUI: HiDPI support including application icons and optional unscaled HiDPI output on Mac OS X (including 3D acceleration)
- GUI: Hotplugging support for SATA disks
- New, modular audio architecture for providing a better abstraction of the host audio backends
- USB hard disks
- Support for the NDIS6 networking framework on Windows (default on Vista and later)
In addition, the following items were fixed and/or added:
- VMM: improved timing on Solaris hosts with older VT-x hosts without preemption timers
- VBoxManage: when exporting an appliance, support the suppression of MAC addresses, which means they will be always recreated on import, avoiding duplicate MAC addresses for VMs which are imported several times
- USB: added USB traffic capturing
- Made resizing X11 guests work more reliably
- API: block the removal of the current snapshot if it has child snapshots (only relevant for VMs without snapshottable hard disks, their presence always prevented removal), which resulted in VM config corruption
- API: mark VM configs with snapshots but without current snapshot as inaccessible, as this combination is nonsense
- API: fix information for some automatically generated events (only with XPCOM, Windows host was not affected), which caused errors when getting some of the attributes over the webservice (bug #12379)
- API: fix crashes in Java API clients using the XPCOM binding, happened with output parameters only (bug #11232)
- API: a number of settings (e.g. network settings) can now also be changed when the VM is in saved state
This professional quality virtualization package must be one of the most powerful open source tools around. The new release is a big step forward, too, but beware, it's a beta, and even the setup program warns you that it shouldn't be installed on a production machine.