Ad-aware, to remove spyware:
http://www.lavasoftusa.com/software/adaware/" onclick="window.open(this.href);return false;
Spybot search & destroy, same stuff:
http://www.safer-networking.org/en/index.html" onclick="window.open(this.href);return false;
Ewido anti-malware, also same. Pretty slow scanspeed here, but can usually find some "ie-cache", even if you dont use IE.
http://www.ewido.net/en/download/" onclick="window.open(this.href);return false;
With RegCleaner you can get rid of all unwanted registry information, remove programs from startup etc.
http://www.worldstart.com/weekly-downlo ... ner4.3.htm" onclick="window.open(this.href);return false;
Dr.Delete. I havent tried this, but I heard its pretty good. With it you can remove the "you cant romeve this file because some other software uses it"-files.
http://www.dslreports.com/forum/remark, ... ~mode=flat" onclick="window.open(this.href);return false;
Just to name a few
