1) I don't know about post-9/11, but pre-9/11 they never even asked for ID. It was a drive-through window: "Citizenship?" "U.S." "Ok, get moving, you're blocking traffic."
2) Depending on which weekend(s) you are here, see if there is a gunshow: [url]http://www.washingtonarmscollectors.org/shows.asp[/url]
3) Snoqualmie Falls, the San Juans, and Fremont.
c) Fremont is the Center of the Universe. Several interesting statues there, including the Fremont Troll, the Rocket, and Lenin. Lots of good places to eat. One of the best art-glass galleries in Seattle, "Edge of Glass Gallery" on 36th. (Also see the galleries downtown while you're near Pike Place.)
b) You can catch a ferry from Anacortes to Victoria, which will take you through the San Juans. At the very least, this route is much more scenic than either the Victoria Clipper hydroplane (nonstop from downtown Seattle) or the B.C. ferries from Vancouver. At the very best, on your RETURN TRIP, I believe you can stop in on the various islands in the San Juans chain. I would recommend the main island, which is San Juan Island, obviously enough. The last U.S./British war, in the 1870's, was fought there (net casualties: one British pig). There are federally-run parks at both American Camp and British Camp. British is more scenic if you only have time for one; American is just a grassland with a few bits of rubble and an educational exhibit.
a) Snoqualmie Falls is an easy 45-minute drive from downtown. Just go straight out I-90 and look for the exit signs; I think it's exit 27.