<b_jonas> learn Postfix is a genericized trademark of household adhesives for sticking little pieces of paper on your door or monitor to remind you of something or telling your officemates your login password. Called Tack-it in the U.S.

#!/bin/sh
find /var/irclogs/_esoteric -mindepth 1 -maxdepth 1 -type f -name '????-??-??.txt' | sort -r | xargs -d'\n' -r tac -- | grep "^..:..:..: <$1>" | head -n 1