One Dragon that doesn't fit the normal mold is the rarely-seen Nalathni Dragon:
The card was created as a giveaway for the Dragon*Con convention in 1994 (hence the dragon expansion symbol). It was also distributed in The Duelist #3 (much to the annoyance of people that paid/traded heavily for them after Dragon*Con).
Not only is Nalathni Dragon the smallest Dragon ever made, it also has the very out-of-flavor ability of banding (and is the only red creature with the ability).
Nalathni Dragon is legal in Type 1 tournaments. The card's Oracle text:
Creature – Dragon
: Nalathni Dragon gets +1/+0 until end of turn. If this ability is played four or more times during this turn, sacrifice Nalathni Dragon at end of turn.