REXX/VSE
- Product page, including support information and samples.
- http://www-03.ibm.com/servers/eserver/zseries/zvse/support/rexx.html

CICS Rexx
- Language and development environment.
- http://www-306.ibm.com/software/htp/cics/products/rexx/

Jaxo: Rexx for Palm OS
- Product description, including downloads and free runtime.
- http://www.jaxo.com/rexx/

uni-REXX
- An ANSI standard implementation for UNIX systems. Free sample code library.
- http://www.wrkgrp.com/unirexx/

BREXX
- Free interpreter for Unix, MSDOS, WinCE and Amiga. By Vassilis N. Vlachoudis.
- http://ftp.gwdg.de/pub/languages/rexx/brexx/html/rx.html

Rexx Anywhere
- Writing portable Rexx execs. By Dave Alcock.
- http://www.planetmvs.com/rexxanywhere/

BeBRexx
- BeOS port of BREXX.
- http://www.bebits.com/search?search=rexx

r4
- Classic Rexx language interpreter for Windows, from Kilowatt Software.
- http://www.kilowattsoftware.com/r4Page.htm

S/REXX
- UNIX implementation from Benaroya. Graphical debugger available.
- http://www.sedit.com/rexxgrph.html

KEXX
- Dialect used in KEDIT (XEDIT-like editor). Summary by Rex Swain.
- http://www.rexswain.com/kedit.html

REXX/imc
- Open source Rexx interpreter for Linux/Unix.
- http://users.comlab.ox.ac.uk/ian.collier/Rexx/rexximc.html