In the flashback for Elliot's vacation, his "old friend" is uncredited guest star Adam Baldwin. Baldwin and Christian Kane starred together in season 5 of Angel. Baldwin also starred in Firefly, another show from the Whedonverse.
The Spruce Goose is housed at the Evergreen Aviation & Space Museum, in McMinnville, Oregon.
In the audio commentaries on the DVDs, the show runners mention that they like to refer to a sidekick or henchman as a "Busey," in reference to actor Gary Busey playing that role in the film Lethal Weapon. In this episode, the villain's henchman is named Samuel Busey.
The fifth season starts with the team moving to Portland. The series actually had been filming in the Oregon area since season two.