The incredible design and data teams at SimpleGeo  and Stamen , known among other things for Polymaps  and Cabspotting , recently teamed up to tackle a data set only the wonkiest of us could love: San Francisco's Pavement Condition Index. I assume Neal and Michael at the San Francisco Bicycle Coalitions's Good Roads  pothole fixin' Superhero HQ  have already checked this out and gushed over the results.
For best results, click through  to the Polymaps website to utilize the fully interactive map feature that allows you to zoom in to your block. While there is some lag in PCI data on Data SF, i.e. Valencia Street from 19th to 15th and Divisadero's face lift don't show up accurately smooth, this is nonetheless an amazing map.
I wonder if the SimpleGeo and Stamen team would consider an even bigger challenge: How about mapping the real-time NextMuni data  set? I don't know nearly enough about programming, but I would imagine it's geometrically more complicated. Tell us what you think of this map and what other hypothetical maps you'd like to see in the comments.