Vitorbalbio has posted a few of his Blender Game Engine works over at Blenderartists.org. The quality of the work is amazing, using a lot of the newer features and tools of the game engine. There's some nice pictures to look at, and the main piece, entitled 'Ruinas', can be downloaded as a .exe to view and explore for yourself in realtime.
All of the works shown by Vitorbalbio use the recently intergrated video texture player, which has now been upgraded to allow for realtime reflections. The 'Ruinas' demo can be downloaded from here, it features animated water with realtime reflections and a very nice ancient ruin environment (press space bar to enable fly around mode).
Theres two other works shown, but with no downloadable runtimes. One room shows a mirror on the wall, while the other has a very nice reflective floor (see the pics below).
Theres more images and information on the thread at Blenderartists.org here.