Barnes & Noble is rumored to be working on a dock for the Nook Tablet, with a release date of sometime this year. But it looks like at least one company is going to beat them to the punch.
ReaderDock has a docking station for the NT in the works (as well as one for the Kindle Fire). They debuted the N-Station in early January and garnered much positive press. This dock is equipped with 2 speakers and it can charge the nook Color or Nook Tablet while in use.
It can firmly hold the NT in landscape or portrait mode and it can be tilted to display the tablet at several different angles. The N-Station looks to be designed more as an audio station, but the many different viewing angles should make watching a video more pleasant.
You can pre-order the N-Station (or the dock for the Kindle Fire) on the ReaderDock website for $55.