I started a project on Monday, August 17th. It may go well, it may die a quick death, I dunno. But here goes.
Each day, not counting Sundays, I'm going to watch one episode of Doctor Who, starting at the beginning. I'm specifying episode, not story, because each story is made up of, generally, 4 to 6 episodes. Sometimes less, sometimes more, but roughly 4-6.
Here comes the fun ... in the Sixth Doctor's era, episodes were double-length, 45 minutes instead of the usual 22 minutes. So counting each of those double episodes as two, as well as the modern episodes as double episodes, plus movies (Five Doctors, the Cushing movies, etc.) as four episodes, there are currently over four hundred episodes on dvd.
So, if I watch one episode per day, taking Sundays and major holidays off, there is enough material already on my shelves to take me though December 2010. Add in whatever is released between now and then, and it'll be even longer.