I just downloaded JHymn and I am really excited about it.
I love the iTunes music store, but I also love my TiVo and the ability to listen to music on my computer. The only way to listen to music on TiVo is to convert all my aac files to mp3 which translates to burning a cd, then ripping them to mp3. Yuck.
Well JHymn handles all that. It actually does MUCH MORE than what I want it for. It actually removes the DRM from the aac files completely and can convert it to mp3 (or keep the same m4p extension w/out DRM) without any loss in quality. That will allow you to listen to your aac files on an unlimited number of computers. Pretty nifty.
Read the Interview where the author discusses his program.