Trivia: In the scene where Samantha Carter is about to release an EM pulse in the room in an effort to discontinue Urgo's annoying appearances, Urgo is protesting his "demise" and trying to prove he won't bother anyone anymore. He says, "What about this?" and changes into a younger man in military uniform. "Can you resist this?" he then asks before he switches back to his familiar form. The actor playing Urgo, Dom Deluise, is actually replaced by his son, one of the directors of Stargate SG-1, for this switch.
Trivia: In classic Star Trek, Kirk and Co. travel to an alternate universe where Spock and the rest are evil and Spock has a goatee. In this episode, Daniel travels to an alternate universe where Teal'c is evil and has a goatee. The name of the classic Trek episode? "Mirror Mirror". How does Daniel get to the alternate universe? Through a mirror.
Trivia: When Colonel O'Neil has been sent for a complete examination by General Hammond, Dr Fraiser tells Jack that his "blood pressure, DRE and EEG are all normal." Blood pressure forms part of any medical exam. An EEG (or electroencephalogram) is a recording of the electrical activity of the brain and considering Jack's seemingly abnormal behaviour might be considered reasonable. However a DRE (or Digital Rectal Exam) is a procedure where by a finger is inserted up the back passage to feel for the prostate. Other reasons for this procedure include looking for blood from a intestinal cancer or evidence of spinal cord injury. Given Jack's age its not necessarily an unreasonable thing to do but given the reason he's in the infirmary is because of his behaviour, it seems very strange. An alternative conspiracy theory could be that it's a bit of a punishment.