Instapaper – I’ve been using Instapaper to save longer articles to read later; it’s great when you come across something you want to read, but don’t have time to immediately read it. Beyond simply saving the link for later, it also has an iOS app that downloads the article for reading offline (e.g. while flying). The archive and “liked” lists are also handy for digging up past articles you’ve read; most of these links come from my instapaper likes.
Kerbal Space Program – A sandbox game where you build rockets and fly them around the solar system. It’s simple enough to play without being a rocket scientist, but challenging enough to make successful flights rewarding.
SourceTree – A great, free Git/Mercurial GUI. This has been around for a while as a Mac app, but they only recently released a Windows version.
Combinatory Logic – In contrast to lambda calculus, combinatory logic is an equivalent program representation that doesn’t have explicit parameters or substitution. Instead, combinators are used to implicitly form functions. See also Iota and Jot, which use combinators to interpret any string of binary digits as a program, a simplification of an important component of Godel’s incompleteness theorems.
Lambda Diagrams – A combinatory logic inspired visual representation for lambda calculus expressions.
Digital Physics – Irrational numbers aren’t computable, but modern physics relies on them. If you assume that anything physical is computable, that implies that either our theory of computability is too narrow, or our theory of physics too “irrational”. Digital physics is a general direction of research that tries to find computable models for physics.
Richard Nixon’s treason – While campaigning against Lyndon Johnson, Richard Nixon was afraid the Vietnamese peace talks would succeed, so he convinced the South Vietnamese to pull out of the talks with the promise of a better deal once he was elected president.