The tingly, nauseated physical sensation you experience in the presence of a douchebag or an act of douchebaggery.
I ran into Dylan at the bar, which was totally lame. After how he treated Madison, just the sound of his voice is enough to give me douchebumps.
(n.) A condition which occurs while or directly following the witnessing of an action of or statement by a person who would fit the description of a douche bag. Usually tied to the emotional sensation of being embarrassed on behalf of another person because whatever they just did was packed full of douchery. Sometimes accompanied by the phrase "are you fucking kidding me?" and a sour facial expression.
Josh: I can't come to the party tonight dude, I gotta get my burn on at the gym. Plus I just got that new Dave Matthews. Yeah!
Eavesdropping bystander: Wow. I just got douchebumps.