While we've been sitting, waiting, wishing for the Nokia N900, we missed something very important: It's not a phone. As this Nokia ad shows, it's actually a psychotic shapeshifter. At least I think that's the message they're trying to send.
If you don't feel like watching the whole ad, jump to about 1:50. It's where the truth is revealed. It's also the moment when I began to daydream about the days when ads actually showed the product for more than a few seconds. [Thanks, GitEmSteveDave!]