I was that A-hole last week. I had about a million things going on in the car, traffic was stop and go, I wasn't sure where I was going, my iPhone wasn't talking to me anymore and even though I didn't look at it, I still rear ended someone. I glanced down at the speed and a sneeze for what seems like only 1 second and then ... crunch.
The guy I hit wasn't insured, but it was my fault. He had his house closed on a few days prior to and was sleeping out of his 2002 Monte Carlo. He was on his way to a job and then I hit him. Man, I felt like a schmuck. After i let him use my phone because he didn't have any minutes his, the cop told me to take off and while I was leaving, he was getting a sobriety test done (this is at 7:45AM). I feel bad for destroying his day, car and who knows what else and hope he comes out ahead in this.
Honestly, I really didn't even feel it in my Touareg. I felt a bump or so, but nothing really else. His car was toast though and the only thing wrong with mine was cosmetic damage and parking sensors up front. I can say that the Touareg is built more like an M1 tank than a car.