I have posted several times on the Battlestar Galactica webisodes, with a storyline that bridges the gap between the two halves of the final season. There are some other webisodes worth a visit, including The Recruit. This one tells the story of the Marines who volunteered to be guinea pigs in hopes of gaining powers to make them better soldiers, and is running between the two story arcs in the current Heroes season. They are also running a lot of other quality related material, including another webisode series, Hard Knox. Another fun webisode set is from Chuck, with a series of Buy More Employee Tips. Not all great webisodes are from NBC/Universal; Lisa Kudrow has an excellent new series online called Web Therapy you should take a look at, with all the biting humor you have come to expect from her.