The Pokemon Sun and Moon demo has come out and it brings with it some neat surprises. The best of which is that you can get Ash Greninja for the full version if you finish the demo!
Smaller stuff you get is some stardust, a star piece and a nugget, all items you can sell for in game money, neat but not as exiting as the free Pokemon, which to my knowledge is not obtainable in any other way.
Are you going to try the Demo? or are you waiting for the full version? which are you thinking about? I know I want Moon, it just calls to me more than Sun.