Reinteract might be interesting for all number crunchers and graphics players, provided they don't get pimples from Python: an implementation of worksheets as you know them from Mathematica and Sage, but as a direct Python application based on PyGTK. You can hack in and execute Python source code, edit older source code afterward, and your output in the worksheet will be automatically updated. Downloads are also available for OSX. Unfortunately, PyGTK is not a 1st-class citizen of the Mac environment - it just looks awful with the half-defective controls, and the usability is unfortunately not really OSX-like. Someone could port this to Cocoa.
Archive 12. May 2011
A successful Git branching model » nvie.com. Not entirely uninteresting article about distributed version control and branching/merging. Ok, it specifically addresses git and its commands, but the overviews and considerations apply to many points equally to Mercurial and in the deviations the problems are similar enough that the article remains worth reading.
counterclockwise - Counterclockwise is an Eclipse plugin helping developers write Clojure code. And if you already have Eclipse installed, a Clojure plugin might not be uninteresting either, so you can get your daily dose of parentheses.
Typesafe Stack is a distribution of Scala (2.9.0) and Akka (1.1, an actor framework for Scala with various tools for programming distributed solutions in Scala) for easy installation. Additionally, it points to sbt and Scala IDE for Eclipse (use the beta version 2, as this is completely new and the 1.x versions do not work with Scala 2.9.0 and are not particularly good) as supplements. Installers are available for Windows, OSX, and Linux (you can of course install them yourself on all platforms, but some people prefer normal installation paths). And if you want, you can buy support there - and the company belongs to Odersky, the Scala inventor and JVM languages guru. Actually, Odersky could also include his book on Scala programming as PDF (in the first edition, this is also free).
LLVM Project Blog: What Every C Programmer Should Know About Undefined Behavior #1/3. Not only what undefined behavior is in language standards, but also the motivation behind it and what it means for compiler manufacturers.