E.L. Post Manuscript Guide - Notes on papers and correspondence by Post at the American Philosophical Society. - http://www.amphilsoc.org/library/mole/p/post.htm
PCP@HOME Contest - A project to find short instances of Post's Correspondence Problem with large shortest solutions. - http://www.informatik.uni-leipzig.de/~pcp/pcpcontest_en.html
Post's Correspondence Problem - A page dedicated to one of the original algorithmically undecidable problems. - http://www.cs.ualberta.ca/~zhao/PCP/intro.htm
Post's Problem of Creativity - An essay discussing some of Post's philosophical ideas in a biographic setting. - http://www.calculemus.org/MathUniversalis/7/09marci.html
Emil Post - Biography of Emil Leon Post (1897-1954). - http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Post.html