I was in absolute awe last Thursday when I had to go to the Pioneer Square Station to catch a bus to Bellevue. I've attached photos from the Web. Some of the buses here use the same stations as the light rail (commuter trains). So you'll be standing at the same place and sometimes a bus will stop - and other times the train. They both in the underground tunnels.
The other stunning thing about the station was it's design. There's a bit of steampunk going on here. And it's so freaking clean! No noise. No leaks. No grime. No rats. No graffiti. No urine.