In the wake of the Pratt & Whitney settlement (the defense giant illegally sold a bunch of helicopter engines to the Chinese) we wondered who else had been busted for outlaw arms dealing that we hadn't heard about.

We went through the State Department's list — which is long, diverse, and contains the names of both blue-chip companies and sketchy front corporations — to find some of the biggest illegal arms.

To keep it manageable we posted only the biggest within the last six years.

Turns out selling weapons and classified equipment to other countries without a permit is very illegal, but extremely lucrative. Hundreds of individuals are banned from doing business with the State Department for risking the practice and getting caught, but there seems little shortage of others to pick up the slack once they're gone.

A lot like another illegal business, it's almost impossible to prevent.