Crude yet self-effacing pun AND Username seen on various UK-based Bulletin Boards.
For those who don't hail from Essex
, as iMac does, it's a compound of I'm a cunt
The Original iMac Hunt is a renamed Keano, who got tired of the comparisons with ex-Man United leg-end Roy Keane
, even after a different Keane had signed for Tottenham Hotspur