I've done one! I iced the whole sponge in black icing. To make the 'screen' I painted on some iridescent edible paint. I then stuck on squares of coloured icing for the apps. It wasn't perfect, but it was obvious what it was and went down very well with DH.
I think I may have to decline this one. I know I could do a decent effort but I would hate giving a cake to someone if it wasn't 100% the best I could make it. I dont know If I have the time to get it right. I have loads on atm.