Presumably, Josh Johnson's amusing documentary "Rewind This!" is a trawl through the cultural history of the video tape and the people who are still attached to this format. But, more than that, it's a portrait of a certain type of otaku fanboy: those obsessed with B-grade movie schlock. The documentary races through the VHS versus Betamax format war, the development of the video rental economy and how that leveled the playing field for a wide range of low-budget filmmakers, and how the ability to easily watch films over and over changed how people saw them.