There's an incredible new interactive map of all the rivers in the lower 48.
Nelson Minar, an engineer for Google, spent a few weeks creating this vector map. I mean every river--even the ditch behind my house, is included.
If you're the super nerdy type and understand what NHDPLus dataset, D3 Leaflet hybrid, or Polymaps mean, head on over to Minar's post about the project. If you're like me and have no idea what any of that has to do with anything, but love looking at maps, rivers and bodies of water take some time here on this massive zoomable version of the project and check out your local area.
Be forewarned, you might get sucked in for a while.