Brooklyn resident Alexander Chen built this cool, melodic web page that represents New York subway lines as ever-growing strings that are "plucked" by intersecting trains. Best of all, it's built off a live feed of actual train data.

Chen created by mashing up MTA's public API with some clever Javascript, vector graphics (SVG), HTML5 and a dash of Flash, according to a post on his blog. Layered on top of this technical achievement are some pleasing artistic decisions: The passage of time accelerates, so you can easily watch a 24-hour train cycle; ghost trains on long-discontinued lines slip by in the middle of the night; and longer train lines make lower notes when "plucked" than short ones, mimicking a real stringed instrument. Having arrived from Sweden just this past September, Chen has come up with a remarkably ingratiating ode to his new hometown. Let's see if future versions — the ones that come out after the Gotham innocent gets more time underground — stay so precious.