GNU Emacs
- GNU Emacs the GNU Emacs home page. Emacs is a very powerful programmers editor. Supports color syntax, custom indenting and much more.
- GNU Emacs FAQ For MS Windows standalone windows port. You can also use emacs from Xwindows in Cygwin.
- Ange ftp over ssh allows you to ftp safely from within emacs.
- CEDET collection of Emacs Development Environment Tools, includes speedbar.
- Matlab mode how to get a Matlab mode in (X)emacs
- matlab.el latest Matlab mode
GNU Tools for Windows.
- GnuWin32 Ports of some GNU tools to Windows (95 up to Vista).
- Cygwin a Linux-like environment for Windows from Red Hat.
- Microsoft Windows Services for UNIX unix tools ported to Microsoft Windows.
- DJGPP allows you to develop software or use many GNU programs and shells on a DOS PC.

Linux
- Linux Online the Linux Home Page.
- Linux Central sells Linux CDs, books, computers and more.
Perl - Programmer's duct tape
- Perl.com O'Reilly perl page.
- ActiveState Tool Corp. they have a freeware version of Perl for Windows.
- The Perl Journal now available in Dr. Dobbs archive sections.
Utilities
- Ghostscript, Ghostview and GSview allows you to print postscript files to a non-postscript printer. Useful for printing from GNU Emacs for windows.
- Google Code Search I have found this site extremely useful.
- Programmer's Heaven useful site, lots of examle source.
- Scilab numerical software package similar to Matlab. Runs on Linux, Windows and Unix.
- Simtel freeware and shareware software downloads for Windows, Mac, and DOS.