| Weeeeell, I wear a key (singular) around my neck, along with the requisite bone carving, and I think it's just peachy. Saves on lugging a redundant keychain around. And I can't forget it. I do have a tendency to misplace things - for short periods of time, but a key tends to walk, even if knowledge of the lock's locus is absent (just one of those things I guess) - which could be a pain. Oh, and it makes cool 'jingle-jangle' noises when I walk =op
'Course I wear it *under* my shirt ('less I've been chasing the purty rubbish truck), it's on a proper cord, and should I ever have reason to carry >2 keys I would most likely migrate to the catholic key carrier. It's a convenience thing, people.
Now if only the cord was longer, so I wouldn't have to smooch the door to (un)lock it.... | 
