Clearly that would be a big market, but I'm serious about massage. Massage from someone who is qualified is expensive, therapeutic, and out of the reach of most people, especially at the amount that one needs it. Having a proper massage robot that was actually good would be a life changing invention. It's also really hard to do -- you need to combine force feedback with dexterity, knowledge of anatomy, natural language communication & feedback (like ouch, awww, and I slouch to the right when I walk), and probably many more things to approximately anywhere close to a human.
I'd love to have a robot work on my hands at night after working to heap ease my RSI. It would be a game changer.