These glasses are made from a food-safe, BPA-free polymer and it is recyclable (#1), but better yet it is reusable. The glasses are actually flexible and completely shatter proof. Perfect for the pool deck or anywhere else glass is not permitted. $12.95 for 4 - you can't go wrong!
You can order directly from the govino website (they also have decanters, stemless flutes, and stemless cocktail glasses) or I just spied them in the recent cb2 catalog.