Painless, partion-free WindowsXP/Ubuntu dual booting
Wubi is an Ubuntu (Linux) installer that you run from inside Windows and will bring you into the Linux world with a few clicks. Wubi allows you to install and uninstall Ubuntu as any other application. It installs Ubuntu to a virtual disk file without making any changes to your partitions or doing any formats. As such, it should be completely safe to install. Since it is utilizing a virtual disk file on your hard drive, it has the advantage over live cds of retaining changes, installations, etc through rebooting of the system and allowing you to install as much as you want as long as you have the hard drive space to spare. It also boots considerably faster than a live cd, and is almost as fast as a regular installation.
Added Thursday 10 May, 2007.