Windows Power Toys

From MS:

PowerToys add fun and functionality to the Windows experience. What are they? 
PowerToys are additional programs that developers work on after a product has 
been released.

URL: http://www.microsoft.com/windowsxp/downloads/powertoys/xppowertoys.mspx

Ones that I think are useful:

Open Command Window Here

This Power Toy adds an "Open Command Window Here" context menu option on file system folders, giving you a quick way to open a command window (cmd.exe) pointing at the selected folder.

Virtual Desktop Manager

Manage up to four desktops from the Windows taskbar with this Power Toy. (I like the idea of the desktop manager, but in practice I can't get used to it. I now remember using it years ago, and one of my annoyances is still there: it re-orders items in the taskbar.)