One thing about me is that I love airplanes (spaceships also), especially vintage aircraft.  The Museum of Flight at Boeing Airfield in Seattle, Washington has a fantastic display of all types of air and space craft.  If you are in any way interested in this sort of thing then going there is mandatory if you are in the Seattle-Tacoma area.  Plan on spending at least half a day.

The last time I was there, they had a B-17 on site with tours given by an actual 8th Air Force Tail Gunner.  Not too many chances to do that these days.  My favorite part of the museum is HUGE WWI and WWII wing.  There are many aircraft and other memorabilia that is extremely rare.

Here was one of my favorites, a Lockheed Electra.  Just look at that shine.

Other pictures can be found here (click on the B-17 Tail Gun picture):