d21lewis on 22 October 2015
This whole "demo" thing is out of control but it's my fault for not putting more thought into the op.
Yeah, some PS1 demos let you save your game. I played a few. Lots of episodic games give you the first episode for free. Some PS3 games let you test the game out for an hour. Several 3DS games like Rusty's Real Deal Baseball, Ironfall, and that new Pushmo let you try the game and then buy it if you like.
It's cool. Nintendo didn't make something new. Now my two big points:
1. You can play Fatal Frame right now!
2. More games (or every game) should do this!
