Make a case with a touch screen in the size of a 19" club mixer like this one
The touch screen will be on the top, and on the sides of the screen some USB ports, jacks, ... and natturally a on/off and reboot button.
And some cinch for audio in and output(s), to ensure a good audio quality.
Then the DJ can play with a program like Atomix Virtual DJ.
Would be great for me as DJ!