As we sweat our way from office to subway, subway to home, front door to the air conditioner's dial, let us remember another hot day in NYC's history: The Blackout of 1977. We're about to start reading Blackout by James Goodman, which reconstructs moments of the blackout, as well as ponders why the riots occured. Con Ed has been saying that we should be okay in terms of power for this summer - Gothamist hopes that Ohio is watching its power system, given what we know from 2003's blackout.
More on the Blackout of 1977: A Wikipedia article, the Blackout History Project and radio coverage from the time. Here's a Christian Science Monitor review of the book. And Gothamist's coverage of the Blackout of 2003.
Image from the cover of Blackout