Terminator: The Sarah Connor Chronicles
Although this Terminator spin-off series premiered on Fox with strong numbers and plenty of buzz in January 2008, its second and last season averaged a dismal 4.6 million viewers per episode, according to Nielsen. Hulu users are more enthusiastic, ranking it No. 35 among the site's all-time favorites.
Disney XD broadcasts an edited version of this action-adventure ninja-dominated anime cartoon, but it's much bigger in Japan (Naruto comic books have sold more than 92 million copies there) and on Hulu, where it ranks 13th on the most-popular list.
Buffy the Vampire Slayer
Joss Whedon's cult classic predates True Blood and Twilight and survived a network shift from the WB to UPN during its sixth year. Still, Buffy struggled to lure more than 5 million viewers. It died in 2003, its seventh season, but has come back as the 21st-most-viewed show on Hulu.
Despite its $10 million pilot, this loose retelling of the biblical story of King David set in a modern metropolis was dethroned after 12 episodes. The royals are now No. 33 in Hulu's all-time ranking.