A form of high five that requires no physical contact. The two (or more) participants simply look at each other and say "Nice!" after one of them initiates the high five. The way this high five is started is that someone yells out "Hypothetical high five!" after which the participants count three Mississippis before saying "Nice." Friends who see each other often and use this form of high five frequently often develop facial cues instead of counting Mississippis before saying "Nice!" People who have trouble making eye contact with others have a hard time performing this high five and it is often impossible for them to perfect the timing.
"Hypothetical High Five!"
The act (or, indeed, thought) of giving a person a high five without any physical contact, as the two persons are usually across the room from each other and far too lazy to get off their asses. Often occurs after a minor success or simply to display ones awesomeness. The process will many times include nodding to further affirm their collective staggering amazingness.