I would love some kind of game where spoilers on the internet don't affect the feeling of discovery within the game. It seems too easy to just look up game secrets on the internet now, and it's almost necessary to do so in order to 'keep up' with other players (mainly in an MMO type game). I don't know if something like this exists now, or how it might be done.

One idea I've been kicking around is to have some sort of disincentive to posting in-game discoveries online. For example, the usefulness or power of an item is inversely proportional to how many instances of the item have been found. Not sure if this is really feasible in practice though.