I've heard one very interesting thing about a form of camouflage I'd call "deception" --2 things actually, now that I think about it.
First, someone in the Middle East , perhaps only for training purposes, had painted aircraft shapes on the ground at an airfield. This was a bit before precision weapons were a standard item. Those painted shapes were targeted, and attacked in preference to real aircraft parked amongst them. Pilots were going fast,probably strafing, and had little time to analyse the scene, and the painted ones stood out better than the real planes. Nice trick!
And then there's the Canadians. They were the first ones that I saw with a false canopy on the bottom of the plane. Other air forces have picked up that trick and applied it to both fighters and close air support aircraft. It's an odd approach to deception based on human phisiology-- we can pull more positive than negative Gs, so if the canopy is facing the observer, the plane can pull toward the observer (AAA gunner, manpads shooter, etc.) much harder than it can push away without rolling first. USAF A-10s still have them, and I asked a pilot of one if he thought it helped. He said yes, that during training with other A-10s he had been momentarily confused as to the orientation of the other planes.
These are "cheap tricks" and could still be used in these hard economic times.
The US Marines had one F-18 at Miramar a few years back with digital camo, It looked cool, but I don't know if it worked.
If there's a remote possibility that your planes might get caught on the ground, the earth-tone camo seems to make sense.