Jerry Siegel created Superman but didn't retain the rights. He was so mad, he ratted out DC comics to the government!
In 1951, things were not going well for Jerry Siegel. Even though he was part of the team that helped to create the most easily identified superhero of all time, Superman, he was broke enough that he felt like he didn't have two pennies to rub together.
Siegel was so bitter over DC (then National) Comics having swindled him out of money he thought was rightfully his that he sent a letter to the government -- J. Edgar Hoover, to be precise. Keep in mind, comics were not faring well at the time. The general attitude was that they had an overwhelmingly negative effect on kids. So Siegel thought that if he wrote to Hoover, maybe he could enact a little revenge.
And the letter is scathing! Siegel goes so far as to accuse National Comics of paying off journalists to write good reviews. And since it was the '50s, he was also sure to call the lot of them communists and pornographers while he was at it.
Unfortunately for Siegel, he got a pretty boilerplate response from Hoover. In fact, it backfired on him, as there then came some research into discovering whether Siegel was a communist.
Below are the two letters courtesy of Bleeding Cool. Very interesting reads, both, and a fascinating glimpse into the mind of one of comic's best-known creators.
(via Bleeding Cool)