Joke aside I transfered a lot of files inside instant messengers and they worked quite well. Nearly everyone had at least a yahoo/messenger/skype/icq account, which made this rather simple, and, because nobody had the capacity/wasn't insterested/was actually p2p, it was perfectly fine. A bummer if the modem connection went down or you had to hang up because the family wanted to make a call, but hey, it was glorious. (no, this is not sarcasm, it really did work.)