Keep a close eye on the optitrack camera site; they are supposed to be going hot with an optical mocap solution for Siggraph that weighs in at under $5,000. What all it will include hasn't been announced yet, but do a search in the forum for yoshi-mocap. It appears that optitrack has bought or liscenced the program he was developing for use with their first generation cameras, and you can find out tidbits from those threads. Not cheap, but considerably less expensive than the next lowest cost system by Gypsy (and if you go with full body you wind up paying 20k for the Gypsy Gyro suit, instead of 14k for the Gypsy upper body frame). The good news is that advances are being made in Poser's animating capabilities, and those are sparking more interest in its use for keyframing figures. And the more attention, the more resources should become available....