Seattle is a nice place to visit, though nicer in the summer. Took me about 13 hours to get there.
They have one of those city pass setups that gets you into the Space Needle, Boeing Museum, Science Centre, Aquarium and a couple others.
Jimi Hendrix Experience museum - stupid expensive to get in, so I didn't, but one funky building. See the Freemont Troll, Tacoma Narrows Bridge. Catch a Sonics or Thunderbirds game. Go to Redmond and throw eggs at Microsoft.