I had a dream about this movie, which I've already detailed extensively at my Twitter account (@newgroundhog - Follow me, you guys!). One aspect of my dream that I neglected to mention was that the doctor was actually forced to make the Human Centipede by a group who wanted to use it as a weapon in a war-type situation. Like a super-soldier or something, but one that moves very slowly, is severely weakened and has less-than-optimal peripheral vision.
It would make for a compelling sequel. DEPLOY THE HUMAN CENTIPEDE!