First, we had the September 11th hijackers. Then, a copycat in a Cessna tried the same thing in Florida. Don't forget the shoe bomber. After that, the underwear bomber. And then some guy sets his house on fire before crashing his airplane into an IRS building in Texas. Now I'm no more fond of the IRS than the next person, but that still seems a bit extreme.
One you might not have heard about took place the day after the IRS building incident, when a man stole a plane in San Diego after some sort of domestic dispute. He apparently had intentions of crashing it into the ocean, but subsequently changed his mind - perhaps because he couldn't find the ocean. He reportedly refueled in Palm Springs (about 125 miles inland) before getting caught on top of clouds around two in the morning. He called ATC for help, and was talked down to LAX - where he couldn't land on a 2-mile-long runway and had to circle around for another try. Airport police met the plane and reported that he appeared to be under the influence of something, although what I haven't heard.
Oh, and another that you may not have heard about, the so-called 'barefoot burglar', is a teenager in the northwest who likes to steal and crash small airplanes, along with boats and luxury cars.