Usually, you can just look at your friend and realize they've had a little too much to drink. Well, there could soon be a wristband that can confirm your sneaking suspicion.
Students at the University of Washington are working on a bracelet that monitors your intoxication and dehydration levels. The bracelet would vibrate every so often and ask you to check in by squeezing it. Once you check in, it knows you're able to function pretty well and are at the very least conscious.
The video below encourages groups to sync through Facebook, that way they can kind of keep tabs on each other through their phones. While connected, the bracelet can notify your friends if you wander off and don't respond to the check in. Using the GPS on their phones, your friends can go look for you, and as the video shows, they can make sure a sweaty drunk guy doesn't take advantage of you.
Interesting concept, but might not work if every single one of your friends is wasted as well.