People I know
Martin Bohner, PhD
Bonita Lawrence, PhD
Sabrina Streipert, PhD
Nick Wintz, PhD
Jacqueline Godoy Mesquita, PhD
Britt Cuchta
Matt Insall, PhD
Leon Hall, PhD
Carl Mummert, PhD
Peter Saveliev, PhD

Math stuff
Quick-sort with Hungarian folk dance
Patterns that eventually fail
Awfully sophisticated proof for simple facts
How to read mathematics
"The Most Common errors in Undergraduate Mathematics"
Foolproof: a sampling of mathematical folk humor
Math's Beautiful Monsters
Math & Beauty & Brain Areas
Exploring complex functions using phase plots
Good Math, Bad Math
Why are special functions special?
The beauty of roots
"What is a closed-form number?" - Timothy Chow
Mathematical urban legends
Mathematics: What do grad students in math do all day?
Mathematical symbols by introduction date
$\Pi$-base-A community database of topological examples with automated deduction and powerful search.
Random.org random integer generator
A planimeter on Google maps
Complex power towers
Proofs without words
A surprising theorem in complex variables
Parrondo paradox
Omar Pol's toothpick sequence
Too simple to be simple
"My favorite numbers" by John Baez
The mathematics of Tetris
E.W. Hobson's "Squaring the Circle"
Hunting for abstractions in mathematics
Mathematical intuition -- what is it?
What would you ask an all-powerful alien?
Measuring fractal dimension
Hackers and fighters
A statement that is paradoxical if and only if it isn't
Colloquial catchy statements that encode serious mathematics
The mathematician as an explorer
What's the point of group actions?
Irving Kaplansky's "A Song About $\pi$"
The chromatic number of the plane
Mathematicians with street names in Paris named after them
The home of mathematical knitting

Math wikis
Cantor's attic
Proofwiki
exampleproblems.com

Other stuff
West Virginia: The Road to Statehood
The Library of Babel
"Hardcore History" by Dan Carlin
Everything is a remix
The History of English Podcast
Mail merge in Libreoffice