I've done this is for an online Soul Calibur art contest with a copy of Mass Effect as the prize. I still haven't decided if I'm going to enter though... since I don't own an X-Box 360. I might enter anyway, just for fun.
============= Obligatory advertisement:
I've listed my Zombie Survival-Horror Manga: PANDORA End of Days 1 & 2 for sale on DeviantArt online at 400 points or $5 per download! [link]
If you don't buy from DeviantArt, you can also get it for your mobile devices: