Well it's not totally useless - there are a few useful shortcuts...

Windows Key + D - Show Desktop*
Windows Key + E - Windows Explorer
Windows Key + F - Find Files or Folders...
Windows Key + M - Minimize All Windows
Windows Key + Shift+M - Undo Minimize All
Windows Key + R - Run...
Windows Key + Tab - Select Task
Windows Key + Break - System Properties
Windows Key + F - Windows Help
* Requires Internet Explorer 4.0 Desktop Update.

Not all that much there, eh? Well, WinKey allows you to assign your own shortcuts. Dead handy. Recommended for all Windows victims users.