There are a few Companies that have based their Business on Rebol. I have listed the ones I heard of below:

qtaskQtask is an innovative business-oriented Project Management SAAS web platform founded by Russell Mix, CEO of the company. Qtask has officially and completely endorsed Rebol. According to their FAQ:

“Qtask is programmed in 100% pure REBOL. This allows Qtask to be developed faster.”

Productivity and Messaging is part of Rebol’s core technology, so it’s not astonishing that, Qtask, as small business, chose this language and get a technical edge over more well-known traditional languages. Nevertheless, Qtask uses Rebol exclusively on the server side: they don’t want to oblige their client to work with anything else than a Browser. This is the right choice as Rebol’s plugin is not mature, stable and graphically sexy enough to compete with Flash (I wish Rebol could one day, I have a dream …).
Enough talk, if you want to know more and take their 60-days trial go here (I’m not even commissioned for that as they don’t have any affiliates program!). And if you are not satisfied, you can directlymake your complain to the CEO, Russell Mix, directly!

site-assistantRefaktor is a small company founded by a Rebol’s Geek named Janko (you can find him on twitter). I first stumbled upon his blog when wandering about Rebol and distributed system. Refaktor developped several websites based on Rebol like Site-Assistant - which offers a free and paid online Service targeting Webmasters for managing their domain names (you can manage 10 domain names with the free version) - and Qwikitodo, an online to-do-list which doesn’t require any sign-up. His sites also use Cheyenne a full-featured Apache-class web server implementation entirely developped in Rebol.

Refaktor - or rather Janko Metelko - has a deep knowledge of Rebol and he wrote an interesting article on Rebol for distributed systems (I was a bit puzzled by the idea as Rebol is not multi-threaded). He also often write some titbits about Rebol so read him here it may be interesting for pros and newbies alike.

neosystaThis is sent to me by Neosysta that I publish as is:

neosysta is a french startup company whose goal is to design management applications for companies, entirely developed in REBOL/MySQL and to all business areas : industries, administrations, banks-insurances, SMEs-SMIs.

On the one hand, neosysta offers its own online applications, for sale or by subscription (France and International). Two (free) applications are already available : “TinyCalc” (a calculator for demo) and “notline” (a complete application for the expenses management of companies) : http://www.neosysta.com/applications_en.html

On the other hand, neosysta offers to design - on demand - specific applications to final customers, also developed in REBOL/MySQL. First to France and later to International.

Website : http://www.neosysta.com/index_en.html
Contact : http://www.neosysta.com/contact_en.html
In video : http://www.youtube.com/watch?v=3gjCO_14UZM

If you are a Rebol based Business and wants to be present on this page, it’s free but you must send me materials ready to be published (use my email at reboltutorial a[-fake-spammers-]t yahoo.com):
A thumbnail of your website (use askthumbnail.com)
A description of your company. Avoid “infomercial” and be personal (give your viewpoint on Rebol) as much as possible (see why in my article “How to be present on the Internet as Business”).