The act of taking a dose of ambien before getting into your car and driving home for the night. If you arrive home before you fall asleep, you win.

OR

Taking an ambien and then masturbating ferociously to see if you can get your rocks off before the ambien kicks in and you fall asleep with cock in hand.
Frat-Brah 1: Dude, I'm so pissed at my roommate.
Frat-Brah 2: How come brah?
Frat Brah 1: Brah, I came home this morning and my roommate was passed out on our couch with his dick in his hand.
Frat Brah 2: Oh man, sounds like someone was ambien racing.
by Lumberjack Hands March 26, 2012
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Racing against Ambien. Drive until you're around 20 minutes from your house and then pop 2 Ambien. Try to beat it home.
Hey, Matt gots 2 Ambien. Grab your friend and your car, let's go Ambien Racing.
by Your Other Left July 21, 2012
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