In order to save muscular movement and energy, a mental high-five may be performed. To successfully complete a mental high-five, one must count from 3 to 1, then tilt ones head forward slightly (like a head bow) and blink at the same time. Mental high-fives can be performed one to one, or one to a group, which can be incredibly handy when one wishes to high-five everyone in a large group. The saved energy from not having to use your arm can then be used for other more important activities, like sleeping, or playing computer games.
"Dude, that was awesome! Mental high five! 3. 2. 1. Go!"
*Nod and blink*