Useful (and often free) Softwares.
Text Editor: TeXShop.
Online text editor (useful for the iPad and collaborative projects): WriteLaTeX
Track modifications on LaTeX files: latexdiff. (requires perl)
MathIM : online chat with a LaTeX feature.
Free Matlab: Octave.
Graph theory: iGraph and Networkx. (Click here for a walkthrough to install igraph.)
Numerical analysis with Python, Scipy/Numpy.
Great text editor for programming, Sublime (not free).
This website's engine, Drupal, and useful extensions:
- Biblio: to manage articles and references.
- Views: to display content using a query.
- Internationalization: to manage a bilingual site.
- DruTeX: to typeset LaTeX code in html.