I'm really looking forward to No Mans Sky.
18 quintillion possible planets. To put that into some kind of perspective, if a new planet was discovered every second, it'd take 585 billion years before they're all discovered.
It's an MMO. When you start the game for the first time, your spawned onto your own planet, a planet that has not yet been discovered.
If you discover a new planet, you're credited with that discovery and everyone who visits that planet later will see your name.
Below is a good discussion on what's know about the game so far: