PSTricks
- Access PostScript capabilities inside (La)TeX, by Timothy van Zandt. Site contains documentations, bugs list, and examples of application.
- http://tug.org/PSTricks/

Journals TeX and LaTeX Packages
- Includes packages for Acta Informatica, Archive for Mathematical Logic, Distributed Computing, Inventiones mathematicae, manuscripta mathematica, Mathematical Programming, Mathematische Annalen, Mathematische Zeitschrift, Numerische Mathematik, Probabilit
- http://www.springer.com/east/home/math/math+authors?SGWID=5-40017-2-94399-0

MusiXTeX
- Created by Daniel Taupin, Ross Mitchell, and Andreas Egler, the package offers a set of macros and fonts that enables TeX to typeset music.
- http://icking-music-archive.org/software/indexmt6.html

Xy-pic
- A free package for typesetting graphs and diagrams in LaTeX, AMS-TeX and Plain TeX using the principle of logical composition of visual components. Presentation, samples and download.
- http://www.tug.org/applications/Xy-pic/