(Farthest left, between the last stick figures and the radar dish [link to location])
Javascript, with the image broken into chunks. It streams the images in as you move, which is why the page loaded so surprisingly quickly.What's the tech used, anything clever?
The comic image (with a hole in it) is layed over the javascript'd area nicely.
It is clever design-wise how he made it seem like a completely ordinary comic (and the page loaded as fast as a normal comic), so you have no clue until you read the tooltip and try dragging, not knowing what to expect.