Back in October 2006, I wrote that I used Copernic and Google Desktop. Search Time has moved on and now I use Agent Ransack. Google stopped supporting Desktop Search in September 2011, and well, Copernic is a $49.95 product. I’m not against paying for software, but I prefer free.
So now I’m using a product called Agent Ransack. It’s the “free” version. Agent Ransack is fast enough for what I want. The only thing I wish it would do in the free version would be for it to scan compressed files (ZIP, CAB, RAR, 7Z and the like).