MTA Conductor by Alexander Chen.
Based on Massimo Vignelli's 1972 subway map, Alexander Chen's MTA Conductor engages both the transit geek and the indifferent commuter. The digital representation of the New York City subway system updates in real time and speeds up as time lapses, eventually cycling through to a 24-hour loop of transit patterns.
The highlight of the piece (and the rationale as to why Chen calls the Conductor an interactive string instrument) occurs when the train lines intersect, producing a reaction much like a cello string in both sight and sound.
If you're interested in learning more about MTA history, check out the interactive New York Times article "An Overhaul of an Underground Icon."
Via: Anil Dash.