You've heard of Coke bottle glasses. But you probably haven't heard of Sprite bottle glasses.
That's the concept that Suning Chen from China came up for the "RE-think + RE-cycle" design competition organized by Designboom way back in 2005. I just happened to come across this little DIY project while doing a Google search on PET (polyethylene terephthalate) bottles. (A public relations representative sent me a release on an upcoming Ecogear backpack made out of recycled PET bottles and I wasn't sure what PET stood for).
Naturally, you could make these glasses out of any plastic bottle, but if you really want to be green, you probably have to go with Sprite, Mountain Dew, or Sierra Mist. I'm not sure of the UV protection on these, however.
Anybody want to guess what that ring is (hint: it's not a nose ring)?