The life-size inflatable jumbo jet was impressive, but the military has been doing this sort of thing forever. As proof, check out OObject's list of eight military-grade spy camera fake-outs. [OObject]
Forget fake airplanes, how about camouflaging an entire aircraft factory?
During World War 2, the Boeing plant in Seattle where B-17s were manufactured was hidden under an entire fake "neighborhood" of streets and houses to hide it from Japanese bombers. The effectiveness of this scheme never got tested though, since only a couple of Japanese planes ever reached the mainland.