Tail recursion in REBOL
Proper tail recursion is unusually difficult to achieve in REBOL. Joe Marshall describes the problem and solution. From LL1: Lightweight Languages Workshop.

Ladislav Mecir's REBOL Articles
Several excellent technical articles about functions, context and binding, and the REBOL interpreter. Also dialects and scripts.

Programming Languages and Computation Theory
REBOL features in this course at Clarion University - includes a lex scanner and yacc parsers of the language.

Build Simple Asynchronous Pluggable Protocols for Windows
How to use the REBOL scripting language to create a protocol that works similarly to the javascript:// protocol, compiling and evaluating arbitrary REBOL statements and displaying the results.

How to use 'bind and when ...
Enlightenment on the troublesome concept of 'bind.

REBOL and RMAIL in Emacs
By Sterling Newton. If you spend half your life in Emacs and deal with RMAIL then maybe this article can make your life a little better.