I think it's a tail feather, about 25 cm long, possibly from a raptor, but I'm not sure. I looked on several web resources, and wasn't able to match it to any common raptors in the area.
We're right in the middle of bird migration season, and here on the Pacific Northwest coast we're right along one of the major North American migratory routes. We get all sorts of strange birds this time of year. I wonder if it's something exotic?
Any birders know what it is?
UPDATE: My downstairs neighbour Parker identified it for me as being a ring-necked pheasant. Bingo. And here's a similar bird. Darn, I was hoping it was a raptor.