Saw this RT'd onto my timeline on Twitter...
http://www.badbat.co.uk/p/submissions.html
I haven't dug much deeper, but they do warn up front that there's no cash prize/fee and your takings are dependent on how many involved/ticket sales etc.
Seems like something that might be good if you want to collaborate, and see something of yours maybe performed on stage. Not 100% sure I'm entering, but it sounds alright.