They added another dimension onto video games.
Has anyone heard of the game Achron? It's a time traveling RTS. It looks interesting, to say the least. I'm really tempted to buy it and start playing the beta.
They handle time with "timewaves". Basically, if you travel to the past and do something, it won't immediately take effect. There is a graph showing waves of change ("timewaves") and things won't change until the wave hits the point in time you have your perception on.
From just reading about it and watching the videos, it seems like it's going to make my head hurt. But maybe that's just because I've been playing too much Starcraft recently and am trying to interpret it through the lens of that. It seems to be slower pace than SC, which I think is a good thing.
The only thing I don't really like is the graphics. It looks kind of crappy.
But who knows, that might change later in development. Or not. But as long as time travel works, I'll be happy.