Favorite thing about Seattle that you can't find anywhere else?
I'm not sure why you'd want to, or really why we need this one, but you definitely can't find another gum wall like the one at Pike Place Market.
Favorite places to eat, drink, and play in the city?
Ivar's Acres of Clams, Skillet Diner. My favorite place to drink is anywhere you can get some local beer or wine—thankfully, you've got some options.
One thing a Seattle visitor shouldn't miss?
Hop on the ferry to Bainbridge Island and get the best views of Puget Sound, Mount Rainier, and the Olympics. The best $9 tour you can get in the city.
Something in Seattle most people don't know about?
Check out the Waterfall Garden Park in Pioneer Square, which is also where UPS was founded.