Put this on your "to read" list: Are Software Patents Evil? by Paul Graham
This is, by far, the best essay I have ever read on software patents and patent trolls. While you/I may not agree with every point he makes, he does an excellent job of explaining the issues and arguing his points. Well worth the read.
He does say one thing that makes me twitch funny: "We tell the startups we fund not to worry about infringing patents, because startups rarely get sued for patent infringement." Yikes...not the kind of statement I want quoted against me in a deposition. ;)
I also encourage you to read two of his other essays: How to Start a Startup and How to Fund a Startup.