this is literally the exact same reason delicious had tags.

i had a text file of the format "url #notes\n" and the notes were pretty short. so i'd write "url #wifi #linux" or whatever.

so a friend asked, "have you heard of this wifi thing?" and i said "yes, here's everything i collected" and just did 'grep \#wifi links' and pasted it to him.

this later became tagging in muxway and then delicious.