IS is possible to create an executable realtime screensaver from Blender? Or can you just export the game code from Blender and add some lines of code that will allow your Blender realtime work to be lanuched as a screensaver. Then finally compile that code as an exe.?

I hope this helps:

With Windows you can make a screensaver of any .exe you want, just change the extension to .scr and put the runtime in C:\Windows\system32 (under WinXP it is so, if you have another version search for other *.scr and put yours in the same directory)
Next just select your screensaver under Display Properties panel, but you cannot have settings to change.

Try searching on www.elysiun.com in the game forum, once I saw a screensaver made with Blender there.
Or search for "haloparty" a screensaver made by NaN.

Good luck and happy blending

Thanks lusque! Just what I needed.