Big Bad Bird
The MegaWhacker in question hit the hawk shortly before landing in Boise; I was supposed to fly that airplane out. As it taxied in, it became evident that we weren't going anywhere - there was a big hole in the side of the vertical stabilizer, with one huge hawk wing hanging out limply. The crew said that the impact shook the whole airplane. This happened on downwind, at about 200 knots. That's significantly below the MegaWhacker's Vmo (redline) for that altitude, so it wasn't even a worst-case scenario.
Today a friend told me that they're looking at up to six weeks to repair the airplane. Beyond the obvious hole in the tail, there was a fair amount of structural and internal systems damage. It's pretty amazing what a ten-pound bird will do to a fast-moving aircraft.