Steven Pinker penned a fantastic essay in The New Republic exploring how cursing has evolved in the English language, and why the various swear words carry the connotations that they do.

I was particularly amused by the incredibly astute point that swear words seem to defy grammar:

As it happens, most expletives aren't genuine adverbs, either. One study notes that, while you can say That's too fucking bad, you can't say That's too very bad. Also, as linguist Geoffrey Nunberg pointed out, while you can imagine the dialogue How brilliant was it? Very, you would never hear the dialogue How brilliant was it? Fucking.

(via a comment on a post on the Rogue Amoeba blog about swear words in serial numbers, which is also incidentally an interesting read, and which is a problem that my own programs do not suffer from, albeit unintentionally)