That sucks to hear. Happened to me in my KE70 about 10Km's into a 400km roadtrip for a weeks holiday. I was at a turn left anytime onto a main road, when my mate behind me in his Mazda 121 spotted a gap in the traffic and gunned it straight into my rear bumper.
Only damage to mine was a slightly bent bumper. He broke his radiator and lost all of his coolant. Just lucky it didn't happen 300km's into the trip.
I always try and drive with the mindset that all other drivers are morons and are going to do something stupid.