On my first group ride ever, a dog ran under my front wheel - knocked me out, broke my collarbone and my hip - bike was ok with a little ding on the saddle. It took two months to walk again, but after I healed, I found a great Korean Cook Book and that dog and I made peace. Now I've moved to the hill country and we have lots of deer, and occasionally a roadrunner will come out and race me (which is really cool, love roadrunners) but what really freaks me out is the thought of a large rattler laying across the road. Never seen one, but it freaks me out just the same.