Effing Meteors is a cataclysmic world-destroying physics Time Waster
You're looking at a side-view of a planet, complete with its layers of atmosphere. Above the planet, in space, there are meteors. These are hurtling towards the planet, but they're often not large enough to survive entering through the atmosphere, so they burn along the way.
Your job is to destroy the planet; or more specifically, destroy all living organisms on a given planet. You can do this because your cursor generates a gravity field. So you click one meteorite and hold; soon, that single meteorite starts attracting other meteorites in its vicinity and grows into something larger – a planetoid. Now when you smash that into the planet's surface, it does survive the atmosphere and generates quite a shock – perhaps even enough to destroy the population of that planet.
Once you destroy a planet, it simply "revolves", revealing a new planet. Each planet is different: Some planets shoot back; and there's a planet with dinosaurs that run away from you, and then flying saucers enter the picture and it all gets a bit hard to explain.
Bottom line: This is a really fun game, with innovative graphics. And sometimes you can win a level by simply doing nothing!