Actually, this isn't a new idea. I thought of it a couple of years ago and posted it here only to find that someone had thought of it before (of course) and someone had even made a crude prototype. They posted a picture of it. It was a flat mannequin, IIRC. made of fiberboard or seme such and probably hokked to the PC using the serial port. It didn't have full jointing obviously, but the person stated that it worked. The thread may still be here somewhere if you want to undertake the daunting task of trying to find it. A number of years ago, there was a gaming accessory for one of the consoles I think called perhaps a "Power Glove" that was a skeletal glove that allowed hand positioning input. I imagine that the basic technology exists to create a kind of body skeleton that would allow direct "Pose It Yourself" input which would be even more fun. I think it all probably boils down to economy of scale. Someone could cook up a homebrew model of something but getting the kinks out, getting a manufacturable design and being able to afford making enough of them to keep the price reasonable is the challenge. An of course, you have to sell enough of them. Figure out how much at least a thousand or so Poser users would definitely pay, factor in the possibility of a Poser 5 "it doesn't work on my machine, it's crap don't buy it" nightmare, etc.It's definitely not a project for the weak hearted or those with shallow pockets.

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken