Power for an mp3 player?

I'm going to pick up an auxiliary input attachment for my 05 coupe. I want to put my Rio Karma in the cubby hole in its dock. I'd like to supply power, so the battery doesn't drain. Is it possible to plug some wires into the fuse box or something? I'd rather not splice into the wires for the cig lighter.

Ok, I'm going to use an add-a-circuit as shown here. Is there an open fuse I can use so I don't have to unplug my radio? I'd just feel a little bit better if my mp3 was powered on its own circuit. I don't think the draw would be a problem (5v, 2mA), but it just seems smarter to me.