I just had a look at how babelfish would translate schadenfreude into English (from the German). It was a shamefully clumsy attempt. It gave the English equivalent of schadenfreude as "harming joy". This is exactly wrong in my opinion. The great thing about schadenfreude is that it can be enjoyed by a bystander who witnesses a misfortune happening to someone else. No need to get involved and do any actual harming.
Thus, when we see a pompous, superior and obnoxious woman slip on a banana peel (or better yet, a dog turd) and lose her dignity, we can enjoy a frisson of guilty pleasure... or shameful joy (schadenfreude). The guilt is in the pleasure experienced as a result of the other person's misfortune; not pleasure experienced as a result of actually causing the other person's misfortune.
Of course, schadenfreude is now an accepted part of English vocabulary, it is no longer merely a wanker's aside. (A foreign word used by a wanker in order to impress the reader with his or her erudition.) I have formed the view that some of the traditional forms of humour associated particularly with anglo-celtic cultures are variants of schadenfreude - self-deprecating humour is shadenfreuding yourself before somebody else does it to you; and taking the piss is schadenfreuding your friends before they schadenfreuderate you.