Photoshop CS5 - Wacom Intuos 4 Large - many hours, 1 custom brush of random dots, squeezed along the Y to create a texture.
I quite like the work of Feng Zhu; but even before I saw his concept designs, I've always been keen on sci-fi. I've always read about them, drawn them, restyled them, etc. Some of Feng's works feature walkers too, so I've watched how he shows them and builds up his compositions, and aimed to do similarly.
I think, overall, this has more Bob Ross style happy accidents than I had intended, but it was a great step forward after University where I was only beginning to learn to control values, let alone any full colour paintings.