Tailly is a heart-rate controlled robotic wagging tail (not to be confused with these mood-controlled robotic wagging tails). It's currently an Indiegogo project and $95 will get you one if they meet their $50,000 funding goal (which doesn't look like it's going to happen with only 15-hours left). The concept is pretty basic -- as your heart-rate increases, so does the tail's wagging. If you're dead, it doesn't wag at all. If you wear it walking, it wags a little. If you wear it running a triathlon, it wags a lot. If you wear it during sex, you're a furry.
Hit the jump for a video demo of the tail-wagging action.
Thanks to Jenny Fromdablock (I see what you did there), who was really hoping they were going to make it to manufacture. Well, looks like it's back to jamming wolves down the back of our pants.