Not exactly a bet but something I would possibly buy in a heartbeat: A guitar modeling and synthesis system done right. Including the least intrusive HEX pickup ever.
And while I know it's the unlikeliest thing on earth, I'm actually sort of wondering how something like this doesn't already exist as a serious product. And no, I'm not talking Variax levels of seriousness. I'm not even talking Boss levels of seriousness - but the real serious deal...
Now that modeling is pretty much good enough for pretty much anyone, including some of the most demanding (and delivering) players on earth, guitar modeling could be the next big thing. I mean, guitars got so expensive, bringing multiple ones to a gig is annoying, etc., so if they could be modeled with FAS level accuracy, that'd be a true godsend.