I yell a lot, it sort of jolts a driver out of their comfort zone and forces them to re-examine their actions, especially when they are routine asshats like cabbies, rather than homicidal jerks in SUVs.
Not much you can do when an SUV is being obnoxious, unless you are the type to feel vindicated by a callout and a fistfight.
When I'm going fast in the city (on an avenue in NYC) I ALWAYS ride in the very middle of the street, taking the middle lane when traffic is light, or riding the centermost broken white when traffic is heavier. Turning cars are more dangerous than steadily flowing traffic.
Make sure that the car sees you. Again, yell ("yeo!" or something similar). As soon as they know that you are there, just ride close to them if they crowd you. They usually get skittish and clear out.
Just like bikes, cars depend on the people around them not killing them--they just have a bit more protection, less maneuverability, more speed and more power-- and probably less skill.