Carrying a bottle opener on your keychain has obviously useful applications, but it also means adding considerable bulk to your keychain and pocket. A user at DIY site Instructables solves this dilemma like some sort of thirst-quenching beverage god by carving a bottle opener directly into his house key.
All you'll need to accomplish this clever project is a to-be-improved key, a bottle opener (to use as a guide), a marker, a vice and a dremel. (Oh, and safety goggles so you don't get bits of brass in your eyes. Safety first!) From there it's a pretty self-explanatory process. Mark they key, put it in the vice, and cut away. Then test it. And again. Delicious.
Now you have little to no excuse for begging a bottle opener off anyone. You are the master of your beverage consumption.
Bottle Opener Key [Instructables