Annoying as it is, having the larger corporations become more and more protectionist about their products is resulting in the beefing up the open source communities, rather than having the effect of getting the consumers to open up their wallets wider. It seems that making the Nerd Community grow ever more disillusioned is a good thing for the planet, and Collective Humanity thanks them, as they offer the fruits of their labours for free, undermining the efforts of the software giants and their money generating monsters. (Yes, I am referring to Vista, and BTW, I think the new copyright protection law will have the same effect in the entertainment industry, which could turn out very nicely for us small time content producers who would like to have all the disillusioned folks come our way. PLEASE download my stuff. I won't come after you for it!)
For the longest time, I used to recommend SpyBot Search and Destroy for eliminating unwanted spyware, adware, tracking cookies, and those sorts of things. While I think the work the originator is doing will generate him tonnes of good karma, there are two major problems with SpyBot these days: (1) Look alike programs that totally bugger up your system if you install them thinking you actually got SpyBot and (2) I'm very sorry to say this, but it just doesn't work that well anymore. I ran three different programs this morning, looking for whatever crap was slowing down my machine, and unfortunately, SpyBot performed the poorest -- it reported finding nothing, while AdAware (I just get the freebie, not the "Plus") and the AVG Free version 8.0 virus scanner found a whole mess of things. After clean up, my machine boots in about 1/3 the time it took before.
I also found that AdAware and AVG ran a lot faster, and are much more aggressive with their updates. In retrospect, I'll probably just use the last two from now on.
Unrelated to malicious code, I also have to mention the Open Office productivity suite, which is completely free, and does everything you would need Microsoft Office for, AND convert files into PDF format without having to purchase the Adobe plug in. Kudos to the community which produced that beauty as well.