How about an Infuse for music?
iOS is lacking both a decent music app featuring last.fm scrobbling (like trakt) and apart from VLC, which is delisted at the minute anyway, there is no (decent) app that you can transfer music to outside of iTunes (or downloading directly on the device), which as I’d like to use Linux from now on, would be great.
Seems like two decent markets could be met with what I suppose could just be a reskinned Infuse.