Microsoft has released Microsoft Private Folder 1.0 . This description is from the download page:

"Microsoft Private Folder 1.0 is a useful tool for you to protect your private data when your friends, colleagues, kids or other people share your PC or account. With this tool, you will get one password protected folder called 'My Private Folder' in your account to save your personal files. Download and have your private folder today!

The following hardware and software are required to run Microsoft Private Folder 1.0:

Microsoft Windows XP Home Edition, Professional Edition and Media Center Edition with SP2
Super VGA (800 x 600) or higher-resolution video adapter and monitor

Please note: Microsoft Private Folder 1.0 is provided specifically for genuine Windows customers, and requires genuine Windows validation in order to download. The software is free, and does not come with product support. "