Some good ideas in here for sure. I tend to change the style from squad to squad, while keeping most of the highlights and details in a similar colour to maintain coherency in the army.
Most of them are:
Chaos Black undercoat
Patched base of Goblin Green and Snakebite Leather
Slightly thinned Rotting Flesh over that (thick enough for coverage, thin enough to show the base through it)
Drybrush in patches of Catachan Green
Dark brown wash (Devlan Mud would work, I usually just mix my own)
Trim is simply Boltgun Metal with Mithril highlights, covered in the same Mud wash
Details in Red Gore/Blood Red (around holes in armor, blood trails, MoN sores on shoulders, etc) and Liche Purple toned down with either a shade of brown or black for bruising).
Raised parts lightly drybrushed in Rotting Flesh if the detail is too stark compared to the rest of the model.
Eyes and lenses are Skull White, with a thin crescent of grey at the bottom for depth.
Overall an easy way to get them tabletop ready and dirty looking. Like the look of armour that's so far gone as to be almost like rotting skin.
Effect is the standard rotting flesh look, with slight variations in colour from green to brown. No pics of them around though, the army isn't currently with me :(