3. The Blair Witch Project (1999)
Maybe not the first example of a found-footage spook fest, but certainly the most successful one and the stepping stone to an entire sub-genre that simply wont go away despite having been exploited every which way till Sunday. So virgin was this territory that masterminds Daniel Myrick and Eduardo Sánchez successfully listed the three main actors as "missing, presumed dead" on the IMDb before the films release, and went as far as putting up realistic Missing posters at the Cannes festival.