Recently, I've seen an increasing number of emails from readers and listeners that stumbled into Adware on their Macs. Interestingly, the bad guys are not just distributing these things through bit torrent and porn sites (as they used to) but instead they are infecting users with "helpful" utilities. Usually it involves a user hitting a website with a pop up that explains it just scanned their system (it didn't) and there are big problems (there aren't) and offers to speed up their Macs with some utility or cleaning application they'll conveniently install with one click. The user clicks, enters their system password, and they are hosed.
The problem I had was that I didn't have a good recommendation about where to go when you or a friend stumbles into this bramble bush. I do now. TheSafeMac.com is a website published by Thomas Reed, who is on the side of angels. The site posts news on recent adware outbreaks on the Mac and even has a tool, Adware Medic, to de-cruft an infected Mac. I recommend bookmarking both of these links. I expect at some point in the future you or a friend are going to need Adware Medic. Also, if you do use it, throw a few bucks Thomas's way. He is distributing this tool gratis.