If you've ever forgotten your password or been asked to assist somebody else in resetting their password, there's a lot of different ways to accomplish it. Here's how to do it by hacking the Sticky Keys feature.
Over at the 4sysops blog, they've written up the process of resetting your Windows password by booting off a repair disk, opening a command prompt and copying cmd.exe over the top of sethc.exe. Once you've done that, you can boot back up into Windows until you get to the login prompt, press the Shift key five times, and you'll see a command prompt where you can use the net user command to reset the password.
If the system already has the Sticky Keys feature disabled or you don't feel like copying files around, you can use an Ubuntu Live CD to reset your Windows password instead.