I always thought the way False Dmitriy I's corpse was dealt with was funny. He was a Polish man who claimed to be the assassinated son of Ivan the Terrible and became Tsar of Russia. When he was discovered, he was shot after he broke his leg climbing out of a window trying to escape his aggressors. Then he was cremated, his ashes packed into a cannon and fired in the direction of Poland.
I can contribute the Cadaver Synod. Pope Formosus was found guilty of perjury etc, or rather his propped-up cadaver was, because he had been dead for quite some time. They didn't launch him from a cannon, though. However Johnny Depp did that with Hunter S Thompson's ashes in like 2004.
I am not sure how true this is, but there was this story of a war between the Austrians and the Ottomans. The Austrians got so drunk along the way, that when one shot was accidentally fired, they all freaked out and shot at each other, ultimately losing the fight.
Neat link from that: The history of the fez in Turkey.