Dark back, very leggy, barred tail - dark tail with horizontal dark bars on it. Breast white and brown - looked like brown, er not stripes, but vertical brown feathers or streaky-type marks (I should learn this bird terminology!). Beak looked kind of like it had a dark tip on it.
It was a kind of hawk-like, falcon-like thing. And now that I've gotten all I remember written down, off to the intertubes to search for possible identifications!
ETA: Breast like the ones the merlins are showing, but a tail more like a Cooper's hawk. I'm leaning towards a juvenile Cooper's for now.
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