Originally Posted by
ohmark
One more thought as to something different: depending on your schedule, you could take Amtrak's Cascades from Seattle to Vancouver, stop over in Vancouver for the night, then take the Cascades from Vancouver to Burlington. It's a very nice train, with a route that goes along the coast for much of the trip.
Interesting thought - before I do that, I'll have to check OW car rentals from Burlington to Seattle as I've got a redeye out on the 12th night & will need a car while in Burlington...still, maybe a worthwhile trip to do in a car since I love roadtrips...