I was really close to this guy when I was growing up, though we've been out of contact for the past 3 years. I'm really excited to get him something this holiday season, but I don't have any idea what it should be be. He's 21 and a single father with a 4 year old girl and a 1 year old boy. He has absolutely no time to himself really, but is into electroics and stuff whenever he gets the time. He lives 3k miles away so I can't just offer to baby sit for him or something. My price range is anything under $100. I'd like to get him something "selfish" for Christmas since every dime he makes goes towards his kids.

MP3 player maybe?

video games (if he a game system)
or a gamefly (http://www.gamefly.com/) subscription (kinda like netflix except the offer games)