What unique/innovative game ideas did you like?

Hey!
I'm trying to find a pattern behind Innovation || "newness".
I'm requesting that you guys post references (preferably videos) to games that you found to have INNOVATIVE & FUN mechanics.
The new things don't have to be EXTREMELY ground breaking. Just small things you might like. Even if you don't know if the technique is original to the game you like, let me know!
I'm going to have a lot to go through, so please explain what you enjoyed or post a video.

Ex: MineCraft
A world that you flexibly manipulate in all 3 dimensions

I agree that innovation can be done through "small tweaks".

My main example would be the ever-so popular "Angry Birds", which was heavily inspired by "Crush the Castle". Besides the more casual-friendly visuals, one small tweak that made angry birds more fun for me was the change from the trebuchet to the sling shot. It was more fluid and less frustrating.