I'm in a TMNT state of mind this month... This started off as a speed sculpt, but I'll usually take it further if I like the direction I'm going in. Went through several iterations of this guy, but finally got something I liked.
This is the intial idea, and speed sculpt. If you wish to see the speed sculpt lapse just visit my youtube channel. http://www.youtube.com/user/JMC3D?feature=mhee