Development
Autoconf
Automake
Libtool
Condor
Lex & Yacc
PHP
Python
All about WEB (HTML, XML, XSLT, XUL, MySQL ....)
XUL
Editing
LateX
Analysis tools
Super Mongo
PLplot
PGPLOT
Specific format and related tools FITSIO FITS page IVOA VOTable documentation IVOA UCD list