Since the original thread on this topic had turned into half advertisements and half discussion I decided to repost it.
I've deleted the dead links and added several that were not included.
I'm going to lock this thread since it's not for discussion purposes. If anyone has a link you think should be included, send it to me via PM.
Reptile Basics - Plastic caging
http://www.reptilebasics.com/
Animal Plastics
http://www.animalplastics.com/
Barrs
http://www.herpcages.com/cages/cprice2.html
Cage's By Design
http://www.cagesbydesign.com/
Monster Cages
http://www.monster-cages.com/
Precision Caging
http://www.precisioncaging.com/caging.htm
Big Apple Herpetological
http://www.bigappleherp.com/REPTILE-SUPPLIES/Habitats
Boaphile
http://www.boaphileplastics.com/
Vision
http://www.visionarium.us/index.html
Freedom Breeder - Top Dollar Rack Systems
http://www.freedombreeder.com/
ARS Caging - Top Dollar Rack Systems
www.arscaging.com
Jason's Jungle's caging - I like these cages, and the prices seem to be just right
http://www.jasons-jungle.com/racks.html
Show Case Cages
http://www.showcasecages.com/
Casey Hulse Caging - Go down to Snake Shacks on the front page
http://www.nsreptiles.com/
Custom Wood Reptile Cage Company
http://customwoodreptilecages.com/
J.worlds - Custom reptile cages
http://www.jworlds.net/intro.html
Customcages.com
http://www.customcages.com/
NPI Reptile and Snake Cages
http://www.npicages.com/
Constrictors Northwest
http://constrictorsnw.com/cagessupply.html
Boamaster
http://www.boamaster.com/
Repti-Racks
http://www.repti-racks.com/
Habitat Systems Limited
http://www.habitatsystemsltd.com/
Acadian Enclosures
http://acadianenclosures.weebly.com/