To celebrate the birthday of one William Shatner, Hulu is running a pretty good promotion — every episode of every Star Trek season is available to stream over the service from now until the end of March. The original series, The Next Generation, Deep Space Nine, Voyager, and Enterprise are all available on demand — nearly 700 episodes in all. This applies whether or not you're subscribed to Hulu Plus, though those who aren't will obviously be limited to watching these shows on their computers. Nonetheless, it's hard to argue with the price — if you want to overload on Star Trek prior to the May 17th release of Into Darkness, now's your chance.
Update: As has been pointed out on Twitter, Hulu doesn't currently offer Star Trek: The Animated Series and the original pilot, "The Cage." But if you'd like to watch the rest of the entire televised Star Trek canon, Hulu has you covered.