American Sign Language/Profanity

American Sign Language, the sign language used by the deaf community throughout most of North America, has a rich vocabulary of terms which include profanity. Within deaf culture, there is a distinction drawn between signs used to curse versus signs that are used to describe sexual acts. In usage, signs to describe detailed sexual behavior are highly taboo due to their graphic nature. As for the signs themselves, some signs do overlap, but they may also vary according to usage. For example, the sign for "shit" when used to curse is different than the sign for "shit" when used to describe the bodily function.

Examples

The back of dominant open b-handshape flipped out under chin means "fuck you" or "so what?" Using a middle finger as the classic "flipping of the bird" has the same meaning. It should be noted that these are actually gestures and not actual ASL signs. Some linguists contend that when the middle finger is used directionally, and pointed as someone or something, it becomes a sign. Another common sign for "fuck you" uses an "FK" abbreviation, signed with an f-handshape changing to a k-handshape, which is referred to as a "loan sign". A "loan sign" is when a fingerspelled word is modified to leave out letters, form a specific shape, or move in a specific direction to become an actual sign(1).
The thumb/index finger side of a b-handshape struck against the side of the mouth or chin means "bitch" (contact point is the side of the index finger). "Bastard" can be produced by doing the same sign but locating it on the forehead.
Touching the p-handshape middle finger to the nose tip then bringing it out to "F" (done with one hand) means "piss off", or, literally, “PENIS F”. This sign creates the meaning of “piss off” by combining the sign for "penis/piss" and abbreviating "O-F-F" by using simply one "F".
Holding a d-handshape in front of the body with the index finger pointing somewhat forward and to the left and the palm pointing somewhat down, then shoving the hand quickly down and to the right in an arc as if condemning someone to hell signifies “Damn” The sign properly ends pointing mostly down and off to the right a bit. Doing this sign with an "H" means "hell."
A rather illustrative sign for "bullshit" uses both arms held out, elbows bent, and folded in front of the signer with the right forearm on top of the left. The right hand mimics a pair of horns with the index and pinkie finger. The left hand mimics the "business end" with flapping fingers. However, this sign is not considered part of ASL, but rather invented by hearing people.
The well-known "OK2 gesture, when held with the thumb on top at the level of the chest means "asshole", as seen in the film Mr. Holland's Opus. Another variant is shown in the image on the side. (This gesture is similar to the American English idiom, "sit and spin".)

References

Valle, Clayton and Lucas, Cecil. Linguistics of American Sign Language. Washington DC:Gallaudet University Press, 2001.