Please make sure you explain what each one does clearly.
Do these at your own risk!
In order to perform these you'll need a registry editor such as Resco File Explorer Registry add-in, PHM Registry, etc.
If you need to learn how to edit the registry visit this thread: Detailed How To Edit The WM Registry Guide
EDIT: For a compiled list of all hacks/edit up to Feb. 28, 2008, visit THIS post, thanks to calisoldier83 for the hard work!