Windows Live Local and Google Maps both show a traffic circle at the corner of 156th Ave NE and NE 56th Way, but if you pay the intersection a visit in person, you won't find one. It was replaced with a speed bump in 2005. Why?
I stumbled across the explanation completely by happenstance. There was a small article in the local newspaper that described an accident that occurred elsewhere in Redmond at a traffic circle. A car was driving down the street in excess of the speed limit and failed to negotiate the circle, resulting in the car going off the road. In the flurry of legal action that ensued, somehow the City of Redmond ended up being held responsible for creating "dangerous driving conditions" or something like that. As a result, the City of Redmond went around removing all the city's traffic circles and replacing them with speed bumps.
Apparently, in this country, a city can be held responsible for conditions that are dangerous to people who are willfully violating the law by exceeding the posted maximum safe speed.
Minor league baseball team the Altoona Curve announced a Salute to Frivolous Lawsuit Night promotion for their game on July 2, though it may be that their lawyers subsequently advised against it, since it doesn't appear on their official list of promotions... Perhaps they feared a frivolous lawsuit.