There are 2 videos I would like to show you.
The first is a music video made for Bjork's "All is full of love" by Chris Cunningham. The reason? The video's mood is strangely sublime and tranquil, despite the detail of what's going on. I think that this relates strongly to the theory that posters should be kept simple enough to be understood, but complex on closer inspection - there is so much to look at, that the video is not too slowly paced. The video is based on the love affair between two robots, and while it could easily slip into the cliche look and feel of science fiction videos, it doesn't.
The second is called "History of gaming" by Johnny Hardstaff. Its a motion graphics video with bucket loads of nostalgia for any gamer thats played any game over the last 30 years. Its very well put together, with all the different elements gelling into a single moving timeline. Definitely worth a watch.