The most obsolete infrastructure money could buy - my worst job ever, by Juho Snellman. Awesome story.
A Computational Introduction to Number Theory and Algebra, by Victor Shoup. 2nd Edition. Free PDF available.
Freer Monads, More Extensible Effects (PDF), by Oleg Kiselyov and Hiromi Ishii. “We present a rational reconstruction of extensible effects, the recently proposed alternative to monad transformers, as the confluence of efforts to make effectful computations compose.”
QED Text Editor (PDF, 1970). By D. M. Ritchie and K. L. Thompson. Quite good feature set!
Conjecture is a new approach to property based testing. Sounds very promising!
Biggest image in the smallest space, “Here is a bzip2 file of 420 bytes that uncompresses to a PNG image of 6,132,534 bytes (5.8 MB) and 225,000 × 225,000 pixels (50.625 gigapixels), which, if represented as a pixel buffer of 3 bytes per pixel, takes about 141.4 GB.”
Cooper Hewitt: The Typeface, by Chester Jenkins.