I had a RAT scare the other day, and searched around found this program called Hijackthis, what it does is pretty much generates an in depth report of registry and file settings from your computer, but it doesn't sort out the the safe for unsafe instead it allows you to selectively remove unwanted items from your computer. Here's the link:
http://free.antivirus.com/hijackthis/ just a word of caution, make sure you know what you're removing as you can stuff up your computer if you remove important file's.