3 unavoidable. Been rear ended twice. Both times I was boxed in during rush hour traffic and couldn't get out of the way. Once I was cut off by a truck driven by some illegal immigrants. Had to slam on the brakes and got hit in the back as a result, which sandwiched me in between the truck and van behind me.

That one was fun when the cop showed up and looked at their license (I couldn't even tell what country it was from) and found they were in a "borrowed" truck.

-D