Maps!

http://nationalatlas.gov/streamer/Streamer/streamer.html

Kind of amazing to play with.  The split between local streams in WNY heading to the lakes, or down the mississippi, is pretty striking.  From one side of the hills at Zoar Valley, everything flows to the lake and then down into the Atlantic.  From the other side of the same hill, it flows south into the Ohio, then down into the Gulf of Mexico. 

We've got out own little continental divide and I never had any idea.

Cool.

Well, until it gets eaten.