Serious question: can/do patent trolls go after open source projects? I'm not thinking of businesses who sell/support open source software (e.g. Red Hat), but

Serious question: can/do patent trolls go after open source projects? I'm not thinking of businesses who sell/support open source software (e.g. Red Hat), but would it be a viable "defense" for an indie dev to simply release their project as open source? I've got an idea for a "weekend project" or two that I could conceivably make a few bucks with, or I could release them as open source so that I can at least benefit from the idea without worrying (as much?) about being sued for violating a patent. On the one hand if I'm not making any money from it one would think that the trolls would go elsewhere, but then again... Just looking for a general idea here, I'm not looking for official legal advice here... :-)