Occasionally, he comes across notes and sketches placed between the pages of the books. He scans these and posts them to his Flickr site. Link (Thanks, Seán in Seattle!)
Mark Frauenfelder is the founder of Boing Boing and the editor-in-chief of MAKE and Cool Tools. Twitter: @frauenfelder. Come and hear Mark speak at the ALA conference in Chicago on July 1.
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