One of the better found footage movies to emerge from the international onslaught of them, Rec is a Spanish movie that spawned three sequels and an American remake. The idea on this one is that a local documentary crew are following a night shift fire department around on one of their shifts. When they are called to an apartment house where an old woman is going nuts, they soon find themselves quarantined by the government. They are trapped inside the building with an increasing number of rabid zombie type attackers. As our heroes fall one by one, we finally get to see what caused the plague and it is not at all what I would have guessed.
The zombies in this are definitely 28 Days Later runners rather than Romero shamblers. Their unique origin also gives them some extra points. I've never watched the sequels so I have no idea how well the premise is continued. For a stand alone horror, this one is pretty well done. I would say this is the movie that exhausted night vision as a filming option. Everything after has had to get a CGI goose. Well worth a watch.