At a Glance
This great little freebie does an excellent job cleaning out many different kinds of junk from your PC, including cookies, many kinds of temporary files, Internet toolbars (called Browser Helper Objects), and unnecessary DLLs. It even includes a tool that will free up system RAM by moving data from RAM to a page file on your hard disk, to increase performance.
HackCleaner also includes a nice security tool as well. It will automatically block any Browser Helper Objects from being installed on your PC--a good thing, because some of them are spyware or malicious software.