So what exactly is Sagittarius?
Sagittarius is a powerful and free online game service built with Google App Engine. That means you get all the scalability and reliability of Google’s products right out of the box. And what’s more, Sagittarius is designed to be deployed on your own App Engine account, giving you full control over your game’s backend.
My game Engage uses Gemini (now am porting everything to Sagittarius) and i gotta say it was pretty easy to setup (of-course Willy was there to help me out :)) and the result was great (server browser is pretty nice!)