The HAARP antenna array bears a lot of the brunt of this sort of thing. HAARP has long been a darling of the conspiracy theory set, due to its seemingly mysterious nature and a lot of overheated conjecture. (After watching the Jesse Ventura episode about HAARP, I came to the conclusion that HAARP theories largely boil down to people not understanding what science is or how it works, and a sort of generalized anxiety about government security.)
Chemtrails are showing up in Sandy chatter, too. Under normal circumstances, a passing jet airplane will leave behind a trail of condensation in the sky. These white trails may linger for minutes, even hours after the plane passes, depending on the high altitude weather conditions.
