I'm convinced that Hindi has the very best swearing options in all the world--the most colorful, specific, inventive, and widely varied. I'm sure I will be writing about this here soon and often. For example, check out this page, but only if swearing doesn't bother you, because this is serious swearing:
Hindi swear phrases listed and rated for accuracy
Very early in my readings about India, I came across a fascinating insult: "Villain from somewhere!" Someone--I believe it was Salman Rushdie--made an aside to the reader that explained it for me. The actual Hindi phrase is:
बदमाश कहीं का! [Badmaash kahin ka!/Villain somewhere of (from somewhere)!]
My Hindi book explains it like this: "'of somewhere,' hence 'of dubious origin'--sharpens the edge of an insult." In a culture where one's background (class, family, caste, reputation) is all-important, to cast it all into doubt in this way--"from somewhere"--is really damning. Americans in particular like to act as if one's background, even one's recent past, don't matter; but this swear phrase reveals the cultural difference.
So next time you want to toss an insult someone's way, and you don't necessarily want them to know they're being insulted, say with the volume that seems appropriate to the situation:
बदमाश कहीं का!