Boing Boing reader Vivienne Gucwa took this shot today, May 30, 2011, as the sun set directly in line with the New York City grid next to the Chrysler Building.  Wikipedia:

Manhattanhenge (sometimes referred to as the Manhattan Solstice) is a semiannual occurrence in which the setting sun aligns with the east-west streets of the main street grid in the borough of Manhattan in New York City.  The term is derived from Stonehenge, at which the sun aligns with the stones on the solstices.  It was coined in 2002 by Neil deGrasse Tyson. 

And, lo and behold, Neil took his own snapshot today, too!