Combined mp3 player and digital photo frame

I was toying with building something that can play mp3 files and display some jpegs with some form of synchronisation and possibly some RGB led light effects.

I could use an arduino attached to an mp3 player board (very cheap option) and use a mobile phone lcd for a screen (again very cheap) but then I looked at how much cheap 7 inch tablets are now... £30!!!

I find it amazing that an arduino touch screen shield can cost more than double that!

Maybe there's an easy way to interface the tablet to an arduino to do the i/o bits and the tablet can do the slide show and mp3 playing...

Just looking for some thoughts...