I'm a big fan of 'atmospheric' scatter terrain. It's perfect for setting the theme of the battlefield, be it World War 2, Peninsular or Dark Ages. So, for our ongoing WW2 Western Desert project I've knocked up some fuel and ammo/supply caches.
The oil drums and fuel cans are mostly 1/48th Tamiya with a few 1/56th resin items I picked up at Bovington earlier this year.
They're painted VMC Russian Green, washed with Agrax then given a quick highlight of the base colour.
The crates and barrels are mostly resin items that I've had for quite a while, so probably a mix of manufacturers. Certainly some Coritani/Magnetic Displays, perhaps some Hovels too? Plenty of companies are knocking this sort of stuff out now - my current fave is Debris of War. They are painted in a range of light to mid browns, washed, then highlighted with the base plus one or two suitable lighter colours, e.g. VMC Dark Sand and Foundry Boneyard Light.