Don't know if anyone has mentioned this, but... http://stage-9.co.uk/ It's a TNG Enterprise D sim. Work in progress but it's pretty sweet to just wander about most of the D.
I love Stage-9! In fact, @Rekkert who posts in the Fanart forum quite a bit works on this. Great stuff!
Building a dolphin ops deck based on the concept designs would put this completely over the top awesome.
The main shuttlebay is reason enough to download it already. Sad we never got to see that in the series!