AFK: Away From Keyboard

In an online chat room, typing "afk" means that you've stepped away from your keyboard to answer the phone or let the dog out or something, so people will know why you're not joining in the conversation even though you're listed in the "who's online" panel.

AFK fit the space I had for the button on top, while "Personal Interests, Non-Computer Related" didn't.

Yes, dear reader, there is life beyond work.