I like keyboard shortcuts a lot and use them wherever I can, especially while developing with Visual Studio 2005, so here are some handy shortcuts for Windows Vista:
Windows key + spacebar: Will show the Windows Vista Sidebar. I like this feature and the possibility to create your own gadgets as well. There's also some to be found on CodeProject as well.
Windows key + x: This'll launch the Windows Mobility Center. Very handy when you're using a laptop.