That sucks man. I've been in 2 accidents, on one I was rearended, and the other, I was in my old High School parking lot, leaving school to go home, and a girl (who was next to my car, leaning in another car to speak to a friend) decided to stop talking to her friend as I was passing, and started to run to either her car, or meet with another friend on the other side of the lot, but I was right next to them, she hit my car instead. I'll just leave that at that unless someone asks for the rest of the story, but long story short, I got off scott-free (or so the saying goes).
And TheJK... HydroPlaning is what happens when there is water on the road, and your tire(s) start riding ontop of the water instead of on the actual concrete, thus resulting in a loss of traction/control, leading to a number of possible results. Or so is how it's always been explained to me.
See:
http://en.wikipedia.org/wiki/Hydroplaning_%28road_vehicle%29 for further information.