Speedtrap.org

No injustice crushes the driving man's soul like falling victim to a speedtrap (no, not even being sent to prison by a military court for a crime he didn't commit). Avoid these travesties with Speedtrap.Org.

With the goal of spotlighting every deliberate police/radar zone in the US, Speedtrap's run by the National Motorists Association -- a libertarian organization founded in '82 to fight against 55mph speed limits, and the tyranny of mandatory polio vaccinations. Each user-submitted entry includes watch times, level of enforcement, and the method by which you'll be busted, e.g., gun, plane, laser, or the terrifyingly capricious "eyeballin". There're also notes from victims, some helpful ("He radioed ahead to a small army of patrol cars at a roadblock"), some helpful for those with a limited understanding of physics ("The speed limit is 45 but you will easily be above this because you're traveling downhill").

Speedtrap also links to relevant laws, ticket-fighting tips, and traffic attorneys -- although if speedtrap's are Soul Crusher #1, cutting a $1000 check to Stan The Radar Man, Esquire, is hot on its heels.