Hi,
I run Ad-aware SE personal and it often finds lots of nasties to remove.
I have found that Spybot:
http://www.safer-networking.org/en/index.html
can find lots of spyware and other nasties that are missed by Ad-aware. Well worth running now and again.
Just as an aside, does anyone here have a Hotmail account? Has anyone found lately that there is lots of ad popups now appearing with the use of Hotmail? I am almost sure that it is Hotmail that is responsible for replacing the 10 or so adware bits and pieces straight after I have run Ad-aware. Hmmph.
Cheers,
Ian.