If you are looking at the specific menu options on a high-definition 1080p physical release or digital download, there are two substantial behind-the-scenes "pieces" or featurettes included on the disc:
: One woman feigns blindness so she can be quarantined with her infected husband. She becomes the only sighted person in a terrifying world of darkness. Blindness [1080p] 2008
: The Doctor, who tries his best to maintain order among the panicked patients. If you are looking at the specific menu
(1080p, ~36 mins): A deeper examination of filming the final sequences of the movie and wrapping up the production. Blindness [1080p] 2008
: The Bartender / "King of Ward 3", the ruthless antagonist who rules by force.