What are the chances of getting sued if i were to draw a couple of famous people and put it online?

Ever since i watched that "Dancing in the street" video, I've been wanting to draw Mick Jagger and David Bowie together. Those two are the one of the biggest stars in the history of musik who have their own full schedule's to attend to, so i seriously doubt that their going to wander on to Deviantart and be like "WTF?! That kid can't do that! Where's my lawyer?!
But i'm wondering if i could get sued oleh the one's who actually make money off the two would flip over that. I'm not making profit from my art, but It could happen. It might not matter if SOPA comes to pass, but it's just in case it the bill falls off the wayside.