My mother used to have a hummingbird feeder outside of her kitchen window. One day she was looking out, just enjoying the view of the hummingbirds when BAM!, a hawk drops in for lunch.
On another occasion, my wife and I were traveling from Missoula to Spokane on I-90 with a friend. I was looking out the window, enjoying the scenery when, just off the road, I saw a bald eagle perched on the carcass of a deer surrounded by a half-dozen or more huge ravens or crows, like a king holding court. One of the neatest things I've ever seen, and I had nothing to record it on.