Well, the Martian Buddy post was correct, the code, 0508 does come in useful! There's a supply cabinet that you can open to get the chain gun, without the code from the internet you can't get into the cabinet, at least to my knowledge. There are a few other emails referring to MartianBuddy.com as well, one even complains about the spam from them.
There's also another URL found in the game, www.ua-corp.com which has a little flash animation that runs. I played my guitar for a while tonight, leaving the animation sitting there doesn't do anything :) It just keeps beeping. I thought maybe after a while it would move on to something else.