I’m not completely sure on this, but I think the fine folks of Premier Guitar invented the rig video. If they didn’t, they’ve done enough of them at this point to be able to claim the title of innovator for sure. The influence of the format can be seen on many a fledgling website.
This month they turned their eye to the rigs of Slipknot’s Mick Thomson and Jim Root. They’re a bit more sparse than I would have assumed, but their music doesn’t really call for a plethora of different sounds, so they seem to be going for the gut.