Good YouTube Copies of the Teaser and Trailer, and a Host Of Images

The Teaser

The Trailer

Another moving picture of the monster can be found here.

Edit: And here:

Lastly, Dennis over at Cloverfield Clues has captured an expansive series of screenshots from the Trailer. You can find them via his blog here. This is the second such capture Dennis has put together, the first being a collection of screenshots from the Teaser here.