On a weekend afternoon a few months back, a pigeon flew into my spokes as I was getting off the Golden Gate Bridge.  Feathers and horrified tourists everywhere.  It was magnificent.  Luckily there is a hose in my garage.

Anyway, the gruesome scene looked a lot like this post-apocalyptic ride spotted by Ramona Wheelright, which means you better either cross paths with a pigeon or get hella creative between now and October's Critical Mass.