Self illuminating strips

  Have you seen them traser glowrings? Keyrings that glow in the dark not powered by light -like illuminous paint. They are powered with some kind of radioactive gas in a tiny glass tube that glows for about 10 years.
  What I'd like to know is why hasn't someone thought of sticking these glowsticks in self-adhesive cases that could be stuck in a whole array of usefull places, for example: light switches (see them in the dark), doorlocks on the home and the car - no more fumbling in the dark, hazard points - no more banging your head in the dark. And that's to name but a few applications. Very cheap to make.