When in a relationship, both partners agree on five people (generally celebrities) that one would allow the other to mess around with if they were given the chance. Celebrities are the norm because the chances of actually meeting a celebrity and subsequently getting the chance to have sex with them is highly unlikely.
"Last night I met Justin Timberlake at a club and we fucked back at his hotel."
"Isn't your boyfriend going to flip out?"
"No way, it's cool. Justin's on my Free Five!"
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A high five given to an employee at a duty free store. This can be done anywhere at the store, but it is preferred that the act be performed at the drive-thru window (if it has one). No purchase of duty free goods is required.

Etymology: The term was coined by David Snyder on January 1, 2006 in Niagra Falls, Canada on a road trip to see Niagra Falls. It turns out that this is the only exciting thing to do in Niagra Falls, especially if you are not 19-years-of-age.
Let's drive up to the window and get a duty free high five from that guy.
by improviduto January 2, 2006
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