^ That's one of the biggest reasons why I keep logs :/
Way too many people give me information I'm supposed to remember via msn - uni group assessment meeting times (and topics!!), phone numbers, party invites, and incredibly funny stuff said on the spur of the moment that you never remember to write down
If I was organised enough to always have pen and paper next to the computer then maybe I wouldn't keep logs, but otherwise I feel it's extremely useful as a kind of "fallback memory"
(everyone's familiar with the "Oh damn, where did they say we were supposed to meet up again?" feeling, yes?)