imaginary bluetooth
An imaginary telephone device popular with riders of public transport, those having manic episodes, paranoid schizophrenics, and just common talk to yourself out loud types.
a. Whoa, dude on the escalator is yakking away to no one and there's no bluetooth in his ear.
b. Imaginary bluetooth in action. Probably on his way to the bus.
Shower Tissue
When you're in a shower and have to blow your nose. You use your index and thumb and replicate the actions of blowing your nose then letting the shower wash the boogers away.
"Man, the other day I Shower Tissued and it flew onto my face!"

UrbanDictionary