At http://www.kubrick2001.com/ you'll find a flash animation in four parts, presenting an explanation - I would not call it the explanation - of the Kubrick film.
It's kind of interesting, but a bit on the long side, so you'll need to allow nearly half an hour to watch all four parts.
I'd never heard of Manhattanhenge (aka the Manhattan Solstice) until a few minutes ago, when I stumbled across some nifty pictures of it at: http://blog.flickr.net/en/2009/07/13/
There is a Wikipedia article about the phenomenon (with another pretty picture) at: http://en.wikipedia.org/wiki/
And then I discovered they have something similar at MIT -- called MIThenge, of course -- which you can read about at: