Aw, man... Pikup- I feel you. Lost a bunch of friends that way too... Worst feeling ever.
Seriously, people need to make themselves available to give drunk friends rides. I do it all the time, and even if I'm sleeping- I've gotten out of bed to go pick up friends that called me. The pain in the ass is much better than hearing they died trying to get home. Don't be a pushover drunk taxi, but you get the picture.
Be safe out there NSers. It only takes once.