Here is a list of several similarities between the Nickelodeon animated series Danny Phantom and Stargate SG-1, which may indicate that Danny Phantom was influenced by Stargate SG-1:
Both Stargate SG-1 and Danny Phantom involve a technological doorway to other worlds (Stargate SG-1 has the Stargate, Danny Phantom has the Ghost Portal).
There are also similarities shared by characters of the two shows. For instance, Stargate SG-1 has a main character named Daniel Jackson, while Danny Phantom has a main character named Daniel (Danny) who is Jack's son ("Jackson" sounds like "Jack's son"). Both shows have main characters named Jack and Sam (Samantha). In both shows there is a main character who is black and has a name beginning with the letter "T" (Teal'c in Stargate SG-1, Tucker in Danny Phantom). Both shows have a main female character whose nickname is Val (Stargate SG-1 has Vala in the show's later seasons, Danny Phantom has Valerie in some episodes). Also, both shows have an episode containing an Egyptian-themed villain named Ra (Ra in the Stargate SG-1 season 8 episode "Moebius," Hotep-Ra in the Danny Phantom season 2 episode "King Tuck").
Both shows have beings who can possess or overshadow humans (the Goa'uld and ascended beings in Stargate SG-1, ghosts in Danny Phantom).
Both shows have an episode in which Earth is phase shifted, or made intangible, in order to protect it from a threat from space (Stargate SG-1 season 10: "The Road Not Taken," Danny Phantom season 3 finale: "Phantom Planet").
In both shows, the technological doorway (Stargate/Ghost Portal) is filled with a fluid-like substance when it is turned on (the event horizon in the Stargate, ectoplasm in the Ghost Portal), and both doorways are equipped with retractable doors (the "iris" in the Stargate).
Both shows have a flying vehicle that can fly into space as well as travel through the doorway [the Puddle Jumper (Gateship) can go through the Stargate (episode "Moebius"), the Specter Speeder can go through the Ghost Portal], and both of these vehicles look similar to each other.
Also, the Fenton Rocket spaceship in the Danny Phantom episode "Phantom Planet" looks similar to the spaceship Prometheus in Stargate SG-1.
In addition, both shows have energy weapons, energy-shield-generating devices, and devices that can make people, objects, or vehicles invisible (cloaking devices in Stargate SG-1) and/or intangible ("phase shifting" or "going out of phase" using the "Arthur's Mantle" device in Stargate SG-1).
Furthermore, David Kaufman, who played Mark Gilmor in the Stargate SG-1 season 8 episode "Zero Hour," also played the voice of the title character Danny Phantom (also known as Danny Fenton).
Lastly, both shows were cancelled in the year 2007.
Can anyone else think of other similarities that I missed?
Are there any other shows that have a similar number of similarities or parallels to Stargate SG-1 or the two other Stargate shows?