four bits for a buck

an uneven exchange or transaction, two bits = 25 cents, four bits = 50 cents, six bits = 75 cents, 8 bits = one dollar. These expressions were used early in the 20th Century to talk about low valued things. Such as "He's got a two bit job."

A geeky euphemism for the middle finger. Derived from the fact that if you consider the fingers of your hand to be binary digits, the middle finger would represent the number four in binary regardless of which direction you counted from.