(as a bored and dumb high school student leaning towards cs, i did a lot of thinking along these lines, ended up getting an admin pretty pissed off at me quite a few times

Back in the day when a 3.2GHz pIV was a modern gpu, If you had physical access to an xp machine you pretty much owned it. a 7 char alpha-numeric password I think i broke in about 15 min (6hr max) and a password using alt-# keys would take about 2 months. When CUDA got out to developers i heard rumerings of a program that would take these two months and drop it to minutes on just an 8800 (it worked exclusively on XP LM hashes, those weak as hell ones I mentioned earlier).
Well it has been a few years since then, and i am impressed at another company that not only breaks xp's hashes, but also vista passwords which uses NTLM hashes which are much harder (it takes longer) to get through, and just about everything else.
http://www.thetechherald.com/article.ph ... IDIA-cards
stumbled on this article, looking for a better one.
and found one(the products website): http://www.elcomsoft.com/edpr.html
[quester goes to look for a program that can use 2GB long keys

oh, and sorry for that subject line...momentary lapse of judgment.