You flatter me! ^_^
I use prismacolor markers, or trias (wonderful!), or prismacolor pencils for my colorings. I used markers and ink for this one, or Brisolboard vellum paper. (good stuff, brings out the markers really well, and works well with lesser-qualitly markers as well. ^_^)
WOW! I love this pic! The pose is great, the gun DOES look awesome, and the coloring is really impressive. Lately I've been working hard to improve my coloring technique, and it seems I should print a few of your pics for refs... because I don't know how to color like this! Do you use Prismacolor markers? Or something else?
http://www.side7.com/art/liliwagn/gallery.html