I drove through a swarm of wasps like that once.. I couldn't see a damn thing except for a layer of bug goo on the windshield. The wipers weren't enough, so we had to stop at the next station to clean the crap off. Didn't realize they were wasps til we got out of the car. Glad we had the windows up.
God, I was driving in Oklahoma to visit my sister in college once and had my window down. Everything was great until a 30lbs Cicada decided to bomb headfirst into my arm that was hanging out the window and then join me in the vehicle. Left a freaking bruise on my arm and resulted in a cracked passenger window. Had to reach over and punch the son of a bitch to death.