Chat Transcript Manager 1.0
Unsanity just released a great new application called Chat Transcript Manager that will index all of your iChat and Adium X chat transcripts and allow you to find what you need (text, links, pictures, etc) in a snap.
I won't enumerate all its features, but it's very powerful, very handy to use, and quite useful if you rely on Instant Messaging a lot. I do, and after I've used Chat Transcript Manager since the very early stages of its development, I'm now completely hooked.
So FWIW, I definitely recommend it!