When Sam and Dean go to interview Betty Hagar about being possessed they employ the now famous rock star aliases. Since they already had a Hagar (as in Sammy), Dean became agent Roth (as in David Lee) with Sam completing the trifecta with a nice trivial twist as agent Malloy. Mitch Malloy was briefly the 3rd lead singer for Van Halen before contractual conflicts prevented him from formally signing causing the band to move on to Gary Cherone.
Sam, in the warehouse, uses an antidemon bomb and the shadows of three demons are left on the wall (actually an overhead door). At Hiroshima and Nagasaki the light of the atomic blasts was so intense that it instantly photobleached any dark and noncombustible surface (brick, concrete, stone). People whose bodies cast shadows on these surfaces left permanent unbleached 'shadows'.