In compiling the list of great tracking shots, I can't forget an episode of The X-Files called "Triangle," in which each of the first three acts unfolds as a single continuous take, while the fourth one "wipes" between continuous action. The second act especially, which follows Scully through FBI headquarters while she tries to track her partner down, is close to my ideal of what the extended tracking shot should be: it's suspenseful, it's grounded in the action, and it makes good use of elevators. I should also note that we seem to be in the middle of a sort of real-time renaissance; in addition to Russian Ark, there's the recenct sitcom Watching Ellie, each episode of which covers a half hour in the life of the main character, and of course 24, that really sublime action series where the entire season covers the events of a single day. A mainstream Hollywood thriller that employs the same single-take technique as Russian Ark can't be too far behind. (I'd also like to note that the reel changes, which I'd worried about, turned out to be a non-issue; throughout the entire movie, I only noticed one obvious splice in the film.)