Dutch Submarines describes a very interesting BBC project - building a replica of the first known submarine.  Is the BBC documenting the history of a Dutch submarine?  Well the inventor was Cornelius Drebbel (Dutch) and he built and demonstrated it for King James I (British) on the Thames back in the 1620s.  

Anyway, the boat is effectively a wood underwater rowboat and the page linked below has some great photos and illustrations of the design and operation of the replica.  Good stuff!

  http://www.dutchsubmarines.com/specials/special_first_submarine.htm

Here's a Dutch human-powered sub project. This is a student team and they have a nice looking website with some design information.
Website