It also features the smallest park in the world (Mill Ends park), which I thought was suitably amusing:

I only had one morning of free time (the rest of it being spent in the hotel eating too much food and trying not to get sucked into pointless arguments). Apart from the park, I went to Powell's book store, which is as large as the park is small. Just the SF/F section was about the size of a small public library, and I discovered a lot of books I'd never heard of, and bought a few for an insanely low price.