Oftentimes I find that when I check for errors, I get some registry value that looks suspect (with an ActiveX/COM thing in it, etc). Half the time, if I scan with AVG Antispyware (ewido), it picks up the registry value too.
Just luck I guess.
I wouldn't call it an antispyware program because it doesn't try to detect it. Because malware often uses temp folders ccleaner can be a quick way to clean it up but still its not looking for it. Its great nonetheless.