I've had 4 email addresses for my personal life: @reed.edu (1989-1994), @santafe.edu (1994-1996), @media.mit.edu (1996-1999), and @monkey.org (2000-present). I take some pride that all but the first address still works. But all the old addresses get is spam; 2600 in the last month. That's 2600 spam messages that got through my gauntlet of spam filters. Most are bounce messages for spam that was forged from my name.
I think it's time to stop maintaining those old addresses.