I tap the breaks if someone tailgates me.
Tho I havent done it so much recently, this one dude in a shitty magna with fake bonnet scoops one night thought hed be a real smartass and get so far up my ass I couldnt see most of his bonnet... I lit the break lights up, no breaks just the lights, he $hat himself and wound up spinning out (this was on the highway) which lead him to have a rather nasty encounter with the middle divider. His car was f**ked... he walked away however im sure (he hit the divider with the front left side of his car once as it spun, it bounced off, spun round and went directly ass first into it and allmost jumped over it), otherwise itd be all over today tonight or something.
As I wasnt involved in the accident (He tailgated me then spun out) I kept driving for a few km's then called the cops to go make sure he was ok.
/end random story.