Blender - Creating a Wall of Mailboxes

A huge benefit of computer graphics is the ability to quickly and efficiently duplicate or instance (link duplicate) geometry. This means we can spend more time building and detailing a single object then duplicate it many times to compound our scene’s level of complexity.
But with such an ability it can be very easy for our duplication to feel too perfect; to feel “CG” and fake. To achieve realism we must implement controlled randomization to break up our CG-ish repetition. Mr. Roman employs such intelligent repetition along with his top-notch rendering skills to mesmerize us with gorgeous complexity. In this course, I want to walk you through a fairly simple example of this idea. From start to finish I’ll show you how to create a realistic snapshot of vintage mailboxes!
What You Will Learn:
Modeling: An old-timey mailbox is a pretty simple object to build. Step by step you will see how poly-model each piece, using mirror modifiers wherever possible to save time.
Shading: Old grimy metal is one my favorite materials construct. We’ll use a single image texture to achieve our grime through a combination of glossiness, diffusion, and bump mapping.
Render Prep: After materials are done, we will implement “intelligent repetition” by duplicating a basic asset hierarchy that makes it easy for us to randomize our pieces.
Post Production: A little bit of compositing can go a long way in helping to reinforce and compliment our lighting and photographic appeal.

Homepage - http://cgcookie.com/blender/cgc-courses/creating-wall-mailboxes/