When my wife (Tomebug) and I first signed up on the internet, we were living in Los Angles. Our ISP (AOL) said that we could have up to seven accounts, but the base account - the first we set up - could never be changed. The other six could be added and deleted at will. Mine was going to be the base account so I didn't want something I'd be tired of later or something stupid or cheezie. So I followed the "you've got mail" movie method and used my city - "LA" - and the numbers in our address - "2047."
Now I've just come to like it, so even though I no longer live there I kept it.