I've just finished recording an interview with Hugh Hancock about his latest movie, When We Two Parted, which will shortly appear somewhere on the Moviestorm site. (The interview, not the movie. The movie's already out, and even hit the front page of YouTube!) Previously, I've used various free tools for recording Skype conversations, but they all time out after 15 minutes, which gets to be a real pain, as you have to keep restarting, retaking, and then you have to stitch everything together, and I've never quite got around to buying a Skype recorder.
Tari put me onto CallGraph, from Sedna Wireless in India, which seemed to work really well. You can record unlimited duration calls, it has a nice history function, and it's dead simple to use. It records you and the other person on separate stereo channels, so editing with something like Audacity is really easy too. And so on. And it's free - though the Web site doesn't make it clear whether that will continue when they come out of beta in a few weeks, so I'd advise grabbing it now. [EDIT: the developers say that the basic version will always be free.]
It's Windows only atm, though the FAQ says that Linux & Mac versions are imminent (and you can get a preview version if you contact them).
Well recommended if you record podcasts over Skype.