CCleaner
http://download.cnet.com/CCleaner/3000-18512_4-10315544.html
Eusing Free Registry Cleaner
http://download.cnet.com/Eusing-Free-Registry-Cleaner/3000-2094_4-10521691.html
SuperAntiSpyWare:
http://download.cnet.com/SuperAntiSpyware-Free-Edition/3000-8022_4-10523889.html
Do Not Track Plus (stops companies from tracking your online history/shopping = no annoying ads!)
https://addons.mozilla.org/en-US/firefox/addon/donottrackplus/?src=search