Information from millions of taxi trips provides a telling record of the city’s vital signs. The map shows the average number of pickups for different times of the day and days of week, Jan. – March, 2009.

Another brilliant data and Google Map mashup from The New York Times’ Interactive Graphics desk: Tracking Taxi Flow Across the City.
When I had a life and went out Friday nights, I competed for cabs in the Lower East Side and in the West Village at 1 a.m. Saturday mornings. And let me tell you. It’s awful. Available cabs are extremely difficult to find and your competition is not only ruthless, but often, intoxicated. Not a nice combination.
I’ve often wish there was an app that showed me locations of available and in-service cabs in real time. Or maybe, the better app is to find the drop off points to quickly find the cabs that become immediately available? This CabSense app looks promising.