US rivers in the contiguous 48
Update Oct 2016: interested in a print? I didn't make it, but I've seen this print and it is quite nice.
Maps of rivers, part of a vector tile project at github.com/NelsonMinar/vector-river-map. More information on my blog. See also Mike Bostock's version at higher resolution with a better projection, the Pacific Institute's version colored by flow, a global version by National Geographic, and the Hydrologic Map of Canada by Joy Charbonneau.
Update Oct 2016: interested in a print? I didn't make this, but I've seen this print and it looks quite nice.
The main thing I'm drawing is the NHDFlowline shapefile in NHDPlus, a dataset that originates from the USGS.
I'm drawing all of the flowlines. This includes lots of seasonal creekbeds, arroyos, etc. That's why you see so much blue in dry areas. It also doesn't include places like the Everglades where specific flowlines haven't been defined. I may have bugs with a bit of missing data, too.
My apologies to Alaska, Hawaiʻi, and the rest of the world. I'm drawing all the data in NHDPlus but it only includes the contiguous 48.
There's an artifact in the data that causes blue rectangles and variable density, particularly north of Texas and west of the Mississippi. I believe it's related to how NHD is digitized off the USGS quads.
Please do look to the GitHub project for technical details!