If you've been in the mood for history, as I've been lately, you'll enjoy Elizabeth Graeber's U.S. President doodles. Currently the flickr set
contains 41 presidents, so she has most of them covered. When you are done there, leap on over to her web site
and dwell deep into her illustration portfolio and the inside of her sketchbooks. Don't worry, if you are not back in 48 hours we'll come looking for you.