Windows 7: The Starter and Home Basic editions of Windows 7 are crippled when it comes to customisation. If you want Aero Glass, Aero Peek or just wallpaper switching from the desktop context menu, here's a handy patch.
The small EXE file, created by a "Mr Dusha" and posted by Microsoft MVP Vishal Gupta, patches system files to enable all the personalisation features of Windows Ultimate.
(Note: lacking a Home Basic or Starter machine, we haven't personally tested this out, but from the comments the patch works simply and as promised. To uninstall, Vishal writes you can re-run the patch or type in sfc /scannow at the command prompt.)