Around 2009/10 I remember a particular style of bag being pretty popular amongst fixed gear riders. It was a black backpack with a roll top/flap top and white branding/logo on it, I'm pretty sure the material was similar to the shiny cordura that Chrome makes their messenger bags out of. The manufacturer might have been Japanese, and I'm pretty sure the Mash SF guys used these bags in some of their videos.

Does anyone know what I'm talking about?