So if you've ever seen the movie Minority Report - you'll know all about precognition.
Vista has it.
You want Vista.

So I've been using Vista for probably a year now and if you had to ask me what my favorite things were - they would be all of the security improvements we made (much more secure code due to code reviews, code coverage, penetration testing, ASLR, NX, /GS, heap changes etc.), Superfetch and Readyboost (not necessarily in that order).  Readyboost + Superfetch is amazing . . . the area where I think I've noticed hte most improvement with Readyboost and Superfetch is launching IE / WMP and more precisely loading plug-ins inside of IE like Acrobat reader which used to take forever but is now nearly instantaneous.  And I don't even have a good Readyboost capable UFD . . . I have the Memorex Traveldrive 2GB (NOTE:  The 1GB model isn't fast enough) . . . I'll be getting something faster some day soon for my home machine and my notebook.