Some clever chappie (professor Silver) has designed a lens for your glasses that you can change the strength of the focal distance yourself – ie. no more optician!
He does this by filling a membrane with water. Using in syringe with a dial you can put in more or take out some fluid, customising it to your own strength.

Yes, they’re ugly, but they’re working on that. They want to sell these things in developing nations for as close to $1,- as they can possibly get.