Here's a month later bump with some exciting information:
yer all dum
Cable modem hacking is very much alive. Check out evilgold's link, and the same premise is valid on many other modem types and different networks. I may or may not have been getting 30mbit full duplex speeds for free over the last two years with only a thirty dollar investment (new modem). It may be awesome (if indeed I were doing it).
If anyone want specifics, i'm sure I or the few people who seem to know what they are talking about (cough not murdoc) can go into detail on why this works, how it works, and why it is next to impossible to be caught.