Ebert adds Caché to the Great Movies.
... a thriller that implodes, not releasing its tension in action but coiling it deeper inside. "Cache" on its fundamental level is about a family that becomes aware it is being watched. And not merely watched, but seen.
Some of Haneke's movies have missed the target, but this one hits not just once but again and again. It's one of the best movies I can think of for a movie-discussion circle, where everyone gets together for coffee and toast afterwards and disagrees vociferously over what they just saw.