Still anything can happen on this market. Remember Hercules, maker of monochrome graphic interface of the old PC/XT computers; they are still alive somehow, and produced a brand new product category, the wireless DJ controller. It is ultra-compact: 17 cm by 15 cm sized, and weighs less than 500 gramm - I don't think it will be easy to play it but who cares. Controller data is transmitted via radio waves into the heart of the system, eats two small batteries, and all the rest of the relevant infos can be seen on the picture. Its official name is very simple: Wireless DJ Mixing Controller, and here is its website.