I've been pretty lucky overall - no multi-vehicle collisions. A couple years ago, I was driving on a suburban crescent with the perfectly worst possible slush on the ground - about 3-4" thick, and sort of a thick, greasy consistency with no chunks of ice - just a paste. Anyway, enough excuses... I'd killed traction control on my car because it was causing it to limp along at walking pace and hold up traffic and as I went into the curve, I fishtailed back and forth 3 times, running wide. Riding the brakes, I rammed my car into a tree at about 2 MPH, but still managed to do about $16,000 (!!!) in damage to it. (No structural damage. Crimped hood, cracked headlight, cracked radiator line, split bumper, which contained foglights, some other misc damage front of the engine, and blown steering wheel airbag.)
My auto insurance is through State Farm Canada, because my first vehicle was a motorcycle and they're famously good to bikers. They heard the claim, signed off on it, minus the $1000 deductible on my policy, and that was it. No questions asked, no rate hikes to follow. I'd had my bike around 3 years with them, and the car for just over 1 year, but was over 25 when it happened.