The Idea is to tunnel all outgoing traffic through DNS. Yes, you heard right, through DNS, the Domain Name System, used to translate human-readable hostnames to numerical IP addresses and vice versa.
via dnstunnel.de
Pretty interesting/novel way... Unix admin skills required, but it's probably better that way.
Luckily I don't ever have to worry about this anymore -- I pretty much just use my Sprint 3G USB modem when I'm out and about.