I need some system design help. I want to create a party jukebox. Anyone with an ipod touch or iphone (or laptop or Android) should be able to add to the playlist but not delete tracks already there. With controls over how many any one person can add at one time. Ideally, they should be able to upload their own tracks or choose from the library and previously uploaded tracks. Ideally it should be battery powered so low power, either 12v or 24v. I picture one of the tiny linux boards with a 500Gb 2.5" hard disk, wifi and a passable sound output stage. I think it should just be a case of packaging pre-built modules with some pre-packaged software. Any ideas on the specifics? This is to go with a one speaker PA, using an active crossover and class D amp, running off a pair of 12V M/C batteries. I'm aiming for 6 hours at pretty loud volumes.