TuneUp Utilities is a program that does a ton of things. Defragmentation, clearing useless files, registry fixes, and suggest things to turn off to make your computer to work as fast as possible.
Just today, I received a newsletter for the newest version, 201. Ever since I switched 7, I've been waiting for this version, since 2009 didn't work properly on 7 (only Classic, XP and Vista compatible). 2010 is basically the same as 2010, just redesigned and 7 compatible.
So, without further ado,
check it out. I highly recommend trying it, since it made Vista a ton faster.
Oh, it's a 30 day trial.