One of the best explanations of Schadenfreude comes from the musical "Avenue Q". If you've heard it before, you know what I'm talking about. If not, well, skip it.
Personally, my favorite explanation comes from an episode of Boston Legal. I believe it's episode two, season two, where Alan Shore gives one of his trademark, long-winded, emphatic closing statements. I won't quote the whole monologue (it can be found here: http://www.boston-legal.org/script/BL02x2.pdf) but I will give you a snippit:
Schadenfreude. From the German words, Schaden and Freude, damage and joy. It means to take spiteful, malicious delight in the misfortune of others. We used to dismiss this as simply an ugly side of human nature, but it is much much more than that. Recently a Stanford professor actually captured Schadenfreude on a brain scan. It’s a physiological medical phenomenon. When we see others fall it sometimes causes a chemical to be released in the dorsal striatum of the brain which actually causes us to feel pleasure. If you watch the news or read the papers, which of course you don’t because the Judge said not to, but if you did, you would see the undeniable delicious joy of the media and the public over Kelly Nolan’s plight. I have no doubt that you want Kelly Nolan to be punished.
She married for money, she had an affair, she carried on naked in the pool with her boyfriend. She’s cold, materialistic, unlikable, and it might bring you all pleasure to see her go to jail. But as for evidence to establish that she committed a murder beyond all reasonable doubt? It just isn’t there. The only possible route to a guilty verdict here is Schadenfreude. Thank you.
... I mention all of this because it really has become apparent that I am a frequent and eager victim of Schadenfreude. To the point, even, when I'm having a bad day and I see how miserable and angry other people are around me, I almost immediately brighten up.
Fucked up, huh?
Another example: I love watching how this whole financial mess is going down. When the Dow loses hundreds of points in a single day, I just watch and marvel as everyone flies into unfettered panic.
I can't help it.
Schadenfreude.