A Canadian Towelette is when you dip your balls into a glass of beer (whether it is your own or someone else's largely depends on how drunk you are) and then gently lay them across someone's forehead. This is much easier to accomplish if they are passed out. The mixture of ball sweat and beer will slowly trickle down their face, much like a moist towelette.
"Damn, look at Lee's face! Why's it all wet like that?"
"Aw bro, he was being a dick and passed out so I took his beer, dipped my balls in it and gave him the ol' Canadian Towelette."
"Holy shit! Dude just woke up and took a swig! Haha, what a stupid chud!"
A convenient way to proposition anal sex with a customer when working at a fast food restaurant or even see someone you like in store. If they use the "Wet Nap" provided then they have cleaned themselves up and are ready for action. Simply walk by their table and drop off a Moist Towelette and walk off while making awkward eye contact to successfully convey your intentions.
#1: Hey did that person just drop off Moist Towelette for no reason?
#2: Don't be so coy, wipe yo ass down and meet him in the bathroom shitstall if you want some action.