Which states or countries have stop-sign-as-yield laws for bicyclists (Idaho stop law)? In Idaho (PDF), bicyclists are allowed to treat stop signs as yields, and red lights as stop signs (essentially; see the actual law for details). This seems like a very reasonable approach, balancing the fact that bicycles are smaller, more maneuverable, and less dangerous for crossing intersections against the fact that you still do need to stop at red lights and be safe when going through intersections.

Are there any other states or countries that have similar laws?


  49-720. STOPPING — TURN AND STOP SIGNALS.
  
  
  A person operating a bicycle or human-powered vehicle approaching a stop sign shall slow down and, if required for safety, stop before entering the 
  intersection. After slowing to a reasonable speed or stopping, the person shall yield the right-of-way to any vehicle in the intersection or approaching on 
  another highway so closely as to constitute an immediate hazard during the time the person is moving across or within the intersection or junction of 
  highways, except that a person after slowing to a reasonable speed and yielding the right-of-way if required, may cautiously make a turn or proceed through 
  the intersection without stopping. 
  A person operating a bicycle or human-powered vehicle approaching a steady red traffic control light shall stop before entering the intersection and shall 
  yield to all other traffic. Once the person has yielded, he may proceed through the steady red light with caution. Provided however, that a person after slowing 
  to a reasonable speed and yielding the right-of-way if required, may cautiously make a right-hand turn. A left-hand turn onto a one-way highway may be 
  made on a red light after stopping and yielding to other traffic.
Utah also considered it, but several groups including a large group of experienced bicycle commuters opposed the change.  The main reasons are:


It further designates cyclists as a "different" road user, possibly making it easier to limit our access to the roadway.
It has the potential of increasing the conflicts at intersections (the most dangerous area for cyclists) because cyclists can behave differently than other vehicles, and motorists may not know what to expect.


While I like maintaining momentum, and recognize that I can see farther, sooner than motorists, I believe that being predictable is more important.