This one is hard to pull off. I think the general conclusion a couple years ago in the study that Sean Convery and Matt Franz did was that it was less work to try to own the router or buy your own AS ;)
this is the "you don't have to run faster than the lion, you just have to run faster than your friend," theory. as those who survived to report are a biased sample, it is not well tested. black hats are opportunistic, but not lazy. they look for cracks with mamzing diligence. e.g the recent brilliant post on cracking the xbox <http://www.xbox-linux.org/wiki/17_Mistakes_Microsoft_Made_in_the_Xbox_Security_System>. when low-hanging fruit is unavailable, or when they see a really cool way to exploit the higher fruit, it would be prudent to have done something about it. who cares about openly recursive dns servers? there are easier ways to crack the host. oops! unfortunately, this is not just theory. few talk about the serious routing attacks that have been seen. randy