Several years ago my prescription glasses broke, so I replaced them with cheap non-prescription glasses for about five bucks. They weren't quite as good (I have astigmatism) but they were serviceable. Only recenlty did I get another pair of prescription glasses specifically for computer use. I spent several hundred doillars (even after insurance discounts) and they are not significantly better than the el cheapo ones I have been using. Yes, there is value in getting regular eye exams, but non-prescription cheap glasses work just fine for lots of people (and mine won't get filled with algae after a few weeks).