I'm not sure if this, via Frank Jacobs, is necessarily the best map I've seen all month, but it certainly has to be a part of the conversation. Behold the Mississippi River drainage network, reimagined as a sprawling and somewhat ungainly public transit system:
Ok, so this thing's obviously in need of some connecting routes, but that's nothing a canal here and a portage there couldn't fix. I'd also extend a branch out to Chicago, which is a natural transfer point to the Great Lakes system. But it's pretty awesome, and captures in full the river's unique Flying Spaghetti Monster qualities.