Auditorium Duet - Successfully kickstarted. http://www.cipherprime.com/games/duet
Auditorium is a unique puzzle/music game. Although it can be difficult, it never gets frustrating. You never get the feeling that you're a part of weird science experiment, that you're being tested like some lab rat. It gently flows through you until you find a solution. With the visual improvements, it's being developed in Unity instead of Flesh, and addition of co-op multiplayer it could become even better than original.
Added to the future section.
To the Thread lurkers!
Check the last page for lots of new stuff.