twice. Once my fault...too hot into a corner, went high, panicked, hit brake, sat up and went straight off road. Rookie mistake. Went down in some grass, no damage.
Second time, some old bitch was in a turn lane in front of me, and slammed on her brakes for no oncoming traffic...I slid into the back of her. When I asked why she stopped she said to wait for a turn arrow....the light was green.