Hercules DJ Control MP3 E2 is highly portable and easy to use, the e2 plugs into a PC or Mac via a USB port and instantly unlocks the potential in your playlists
Saw this in Comet Worcester Blackpole today, they had 2 in stock, not sure what stock is like anywhere else as it's not online.
Seem's like a pretty decent USB controller for people who want to DJ as a hobby.
Selling for around £67 on Amazon
Going for around £50 Used on eBay.