Photoblog Citynoise has some classic pictures of New York City over the last century.  My favorite is probably the Lower East Side, taken in 1941.

I lived in the East Village in NYC from 1998 til 2005 and looking at pictures of New York always brings back memories.  So much has changed in the city, even since I came back to Texas, that it's especially cool to see venues that have remained the same for this long.

Here is McSorley's Old Ale House, on East 7th Street between 3rd Avenue and 2nd:

Here, in a user photo by Picasa user Dušan, found on Google Street View, is McSorley's Old Ale House today:

For most of its history, McSorley's tavern was restricted to men only, until it was forced to allow women in the 1970s.

The photoblog Shorpy also has some historical gems.  Here is Chinatown 1906:

This is Mott Street looking toward the Roman Catholic Church of the Transfiguration.  The facades are massive and beautiful.  I'd love to be able to visit this Port Arthur Restaurant and see what Chinese food was like at the turn of the last century.

Here is Mott Street today, in a picture by Picasa user Yann:

Beyond the white sign on the left is Hop Kee, my personal favorite Chinatown restaurant. You can see the Catholic Church of the Transfiguration. The facades have changed but the buildings themselves are more or less the same.

From where this picture would have been taken, the camera is just in front of the Chinatown Fair, an arcade which until shortly after I moved to NYC was host to the world-famous tic-tac-toe-playing chicken.