When Pam, Dwight, and David are on the speaker phone in the conference room with the marketing people in New York, Michael rushes in, announcing that it was his idea and yelling at Dwight. David leans in to the phone and says loudly, "We're gonna call you back, guys" to the marketing people. But neither David nor anyone else in the room hangs up the phone.
At about 12:18, while Michael is trying to talk Dwight into taking the fall for the Golden Ticket idea, the neighborhood filming notice can be seen hanging on the door behind Dwight.
When Dwight, Michael, and Jim are playing with the KGB knock knock joke, they all speak with German accents. The KGB is Russian.