Well, Global Effect is very like Sim City in initial impact. You know, you've got this world and all the tools you're ever going to need and you've got to build it up into a perfect example (or your own interpretation of perfect) of what a world should be.
The twist is that this time, rather than the relatively simple task of Sim City, building cities, your task is to make sure the world doesn't get over-polluted, damaged and all sorts of other things into the bargain.
Global Effect is a novel slant on the 'god' game, but unfortunately there's a severe lack of anything going on to keep you interested in the game. There's also a long list of faults - the main one being that success depends, bizarrely, almost entirely on how many trees you get to grow and little else.
Although the theory behind the game is intriguing - building up a world the right way, instead of the way we've done it - Global Effect is poorly conceived and takes ages to get anywhere in. Damn shame that.