Bike Portland passes along the news:
As part of the public art planned along their Portland-Milwaukie Light Rail project, TriMet is considering something quite interesting for the new Willamette River Bridge — a "sonic bike path." […]
The "sonic bike path" concept is still in its early stages, but at this point, the idea is to create a series of grooves on a 150 foot section of the bikeway on each end of the bridge. The grooves would be placed in such a frequency and depth that a melody would be emitted as bicycle tires rolled over them. As for the song, the artists are considering Simon and Garfunkel's "Feelin' Groovy."
The proposed sonic path would include an opt-out lane (naturally; this is Portland) for people who don't want 60s folk-rock as part of their alt-transit experience. And apart from its intrinsic Keep-Portland-Weird factor it would function as a heads-up to cyclists that the bridge was ending and they are about to be dropped down a ramp into urban traffic patterns again.
Portland: Out-"Portlandia"-ing "Portlandia."
Update (October 2011): Sigh.