After twenty minutes on this c-series Citadel halfling, it looked like this:
I started with spray paint: first black, then brown from the top 35 degrees, and finally a little dusting of white to catch the highest highlights. Over this I did the exposed flesh in a mix of white, green and red with a touch of umber. It reminded me a little of some experiments by Tears of Envy, particularly her great =I=munda miniatures. It needs work still. (I think one more point of colour or heightened contrast is needed, maybe some differentiated or smoothed out metals, and the base needs contrast and a clean, black bevel.) But I'm really into the overall desaturated, inconclusive effect. It reminds me of moleskine paper, Sergio Leone's mud-covered Union soldiers and the Lewis Chessmen, all a the same time.
And it's really fast to do. I'm imagining all my miniatures done over like this now: monochrome but with a couple of very specific details for interest; maybe with different colours or contrasts to distinguish sides or noteworthy pieces. (Maybe colour or detail should be the perquisite of in-game importance, as if spotlights follow the central characters, or vice-versa: maybe importance = monochromatic cypher-dom...) Heroquest miniatures, very characterful but blocky and static by today's standards, would be perfect for this, and the game board has a nice colour palette to borrow from. But I can see Reaper's Bones (and now I kick myself for not getting in on the last kickstarter) taking this treatment well too, and they're cheap enough to risk on the experiment.
What's the point of the experiment? Making miniatures that facilitate better imagining for everyone who's sitting around and rolling dice together. I think that this would be a great way to paint a wargames army, but I'm thinking about D&D here, where getting out of the way of everyone's imagination is key, and where incompleteness is part of what makes it all fun.