Technically you CAN go through port 80. But since your network's so locked down, I bet they also use a proxy for all the port 80 traffic, so you can't just sneak it through. You would have to use an HTTP tunnel, which is a piece of software on your computer that sends regular P2P traffic through port 80 making it look like web requests, and another piece of software on the other side which decodes said traffic and sends it on your behalf. It's very slow, probably doesn't work so well with UDP packets, and you'll set off a huge flag at the firewall (browsing too much
