A while back in IRC masta was looking for another MoI challenge and someone posted a link to the Festo website. Festo produces pneumatic actuators for industrial robotics. The sheer level of detail in the product catalogs is brilliant and I decided then to build myself a robotics object library based on the Festo designs.
Most would have seen masta's MoI models by now, which by the way are gorgeous, but I wanted to do something different, something bigger, and set out with 3 goals:
1. All objects will be modeled using nothing but the most fundamental poly tools which ensures ultimate polygon utilization and clean meshes (helps with goal 2). No booleans will be used period as booleans always create messy meshes.
2. All objects will be UV mapped and textured accurately.
3. All objects will be rigged to facilitate easy posing once combined into completed robots.
I have now almost completed the base meshes for the first component. This component is a linear cylinder actuator. I will actually remove some features from this mesh for the final object as they will become redundant when actually used in a completed robot. The materials are preliminary at the moment and I have to hold off on completing goal 2 as 64bit blender 2.45 un der linux has an issue with the Smart Projections UV Unwrap script at present and it's pretty much a must have for objects as geometrically complex as this. I have tried regardless and if one looks closely you will see that the central cylinder is sporting a bump map for extrusion lines and the end caps have mold dimples as thats how those parts would be crafted (both unfortunately distorted by bad UVs).
Anyway here's some test renders and some screen caps of the mesh:
Almost Complete Mesh ~13500spp:
An earlier render just after finishing basic thread work on piston. Shot as a pair so I could check all details for issues:
Full mesh screen-cap (Blender):
Screen-cap close up of my piston head and nut of which I'm very proud, simple but beautiful
(Blender):
It's taken well over a week to get to this point bearing in mind that I do work so weekdays I don't get to do more than an hour or two.
No more embarrassing threads about why my materials are rendering black for me 
great!!!
...then again maybe it's just the environment it's being rendered in. If that were the case though I would have expected all those dark areas to be blue, reflecting the sky, but that doesn't seem to be the case...