Think Hi-Tech had one of these leeches sucking at him a while back, sounds like a good law IMHO.
http://news.yahoo.com/anti-patent-troll-bill-passes-u-house-huge-013003182.html#!
To be honest, the entire Patent system in US is totally broken. In US you can write a patent on something that does not event exits, like there were patents on time machine or a patent on something trivial like a rectangle (not kidding) - see the Samsung-Apple lawsuit.
US is the only major country that allows patents on software/algorithms.
This maybe a good law against patent trolls, but in reality the entire patent system in US should be seriously rewritten