Check out a page in the Commuters forum. Title: What do you commuter guys look like?

I think on page 5 there is a picture of a guy who had a pretty bad bike accident, he's OK but his face is all cut up, and helmet was impacted. Part of his glasses had to be surgically removed from his head.

The story is a few posts after the picture.

Not an environment I'd likely be riding in, but impact is impact.