A lot of Gamestudio projects have been released, the last one was SüperCan. There is a ton of other commercially released projects which you can find on the main page, the history goes back to A4.

There are also a lot of uncommercial projects which have been released, for example the user mercuryus has a pretty nice list of finished projects.

Shitlord by trade and passion. Graphics programmer at Laminar Research.
I write blog posts at feresignum.com