I record my class conversations with FRAPS; took some time and setup to get the recording/compressing/filing system down, but I'm glad I did it.
Sometimes I wish I could go back and replay critical conversations, not to change history but just to see what the resulting lines would have been. Kind of a "what if?" thought/viewing exercise, no more.
Even just to rewatch what i did
say. I blew through pretty much all the companion/romance stuff with Corso on my smuggler, and most of the Vector stuff on my agent before it occurred to me to start recording these things. Watching other people's youtube videos doesn't really work, because of different conversation paths.