Running XP As Non-Admin

Users Overlook XP’s Non-Admin Security
Microsoft is sparing no expense to spread the Least-privileged User Account security gospel ahead of next year’s Longhorn launch, but a little-known fact—especially among IT administrators and end users—is that the technology is already available in the Windows operating system.

The article references the nonadmin wiki as a good source for information and tools. It is run by Microsoft developers.