Playing a werewolf isn't just for kicks and giggles, as it's part of the main quest in Bloodmoon (you don't have to play one for long; you are presented with the option of getting cured from this "disease"). It's also worth mentioning that a werewolf in the world of Morrowind is designed a tad bit differently than what you may expect based on popular folklore: the moons have no effect on them at all, normal weapons can harm them, and since they suffer from Bloodlust must continually feed or risk starving to death. It's actually quite challenging in that you can't access inventory, talk, or cast spells while wolfed-out. On the plus side, you're a walking tank; werewolves are extremely fast and their claws cause incredible amounts of damage.