The new Microsoft OS “Vista” is out for a while now. No problem for end-users, they can “safely” (notice the quotes ;-)) upgrade their machine with this new toy. But, professional users (who must run specific applications[1]), it is safe to delay the “big jump”.
When you start Vista for the first time, you will face Aero, the new GUI. One of the Aero features is the sidebar. You can add widgets such as, monitors for CPU/RAM/Disk, calendars, clocks, and more!
I found a nice freeware called Vista sidebar which add this feature on a Windows XP desktop. Funny!
[1] VPN clients are a good example