The Discovery Channel Mini SeriesDragons: A Fantasy Made Real is a Mockumentary all about a how dragons could be scientifically possible. There are four types of dragons covered: Prehistoric Dragons, Marine Dragons (Sea Monsters), Forest Dragons (Chinese Dragons), and Mountain Dragons (European Dragons). There are also "Desert Dragon" shown but it was never elaborated upon.
Along those same lines, Sci-Fi's Beast Legends makes a dragon from a mix of real animal parts, and ends up with a creature resembling the Kaiju Varan about the size of a bull.
In Knightmare there seem to be three differenttypes of Western style dragons, based on color. The smallest and weakest are blue and are never actually seen, just mentioned. Greens are the friendliest (in the sense that they are willing to deal at all with humans). Red dragons are both the most powerful and most wildly destructive.
In Merlin [BBC], the (male) dragon lives under the castle in a cave, can talk and knows magic. It can only be controlled by a dragonlord, a people of which Merlin is the last. Dragons are also only born with the help of a dragonlord, who calls them from the egg by naming them.
The episode Eye of the Phoenix has Wyverns. They are a lot smaller and act more like a pack of intelligent, but not sentient, animals. Gwaine mentions that they are distant cousins of the dragons, but it seems wyverns are at least closely related enough that a dragonlord may command them.
In Lost Tapes a "Dragon" appears, but as a variant of the Real Life Komodo Dragon that was thought to be extinct: the Megalania. It eats a Survivor Man wannabe.
Special Unit 2 references European and Asiatic dragons, and prominently features a "Native American" dragon. However, it acts like (and vaugely resembles) the stereotypical European portrayal in terms of behavior, is armored like a Tank and has a taste for gnomes.
Kamen Rider has had four dragon-featuring seasons so far:
Kamen Rider Agito is a chinese dragon based humanoid and the show implies that humans will become like Agito.
Kamen Rider Ryuki has the twin dragons Dragredder and Dragblacker. With the help of Kamen Rider Decade, Ryuki can also transform into a leaner version of Dragredder.
Kamen Rider Kiva has Tatuslot as Kiva's power-up, Castle Doran and his chibi power-up, and Kiva's own Flight Style form.
And Kamen Rider Wizard has an evil dragon monster sealed within him, serving as the source of his powers.
Farscape had Budongs. Giant space dragons which would occasionally eat passing spaceships and were a real threat to interstellar travel. Dead Budongs were inhabited by mining colonies.
Power Rangers: There are number of Zords based on dragons. The most famous would be the Dragonzord, which is aquatic and resembles Godzilla, followed by the Red Dragon Thunderzord, which is modeled after Eastern dragons. Serpentera is also an Eastern dragon. But that's just the Mighty Morphin era. There's also the Dragonforce Vehicle in Power Rangers Ninja Storm, the Mystic Dragon zord combination and Fireheart the actual dragon in Power Rangers Mystic Force, the Dragon Foldingzord in Power Rangers Samurai, and the Dragon Mechazord in Power Rangers Megaforce. Power Rangers Lost Galaxy also has a draconic Zord, though its official identification is the "Condor" Galactazord. On the flip side, Power Rangers Dino Thunder tries to pass off a Ptero Soarer as the "Drago Zord".
In the tv series version of The Dresden Files a dragon appears in one episode and it's strongly hinted that a member of the White Council is one in human disguise.
In Primeval (Season 3, Episode 7), a dinosaur known as a Dracorex wanders through an anomaly into the middle ages, where it is mistaken for a dragon.
Supernatural's budget constraints gave us dragons that could shift between human and dragon forms, and apparently they prefer to be in human form most of the time. Naturally they have heat-based powers, which they use to french fry their victims. They can only be killed by swords forged in Dragonblood, and they work for the progenitor of all monsters, Eve.
One season 10 episode of Stargate SG-1 had a dragon attack the motley crew (SG-1, Ba'al, and Adria) searching for Merlin's anti-ascended being weapon. This dragon was actually a sophisticated technological illusion; beating it required Daniel yelling its creator's name at it.
