There have been some massive, impressive projects done with the Morrowind and Oblivion Construction Sets.

What kind of projects would you like to see with the Skyrim toolset?

Personally, I'd like to see remakes of Battlespire or Redguard. Arena is distributed freely. Morrowind and Oblivion are cheap and can be purchased just about anywhere. But I never got to play Battlespire or Redguard. And from what I understand, neither have the massive world sizes of Arena/Daggerfall, so it is far more feasible to remake them.