Imagine if you combined Mad Max and Star Trek into one game and you¡d probably get OGame. OGame is a strategic space simulation game with thousands of players across the world competing with each other simultaneously.
It runs straight from your browser and requires no installation. You start in the game with just one undeveloped world and your aim is to turn that into a mighty empire that's able to defend your colonies. You defend yourself by waging war against other empires in the age old struggle for resources. You can negotiate with other emperors, create an alliance and trade for much needed resources.
Once you've built up your empire, your next task is to build some defences to protect it all. You can do this by building laboratories in which you can experiment and create the latest in defense shields or some horrible weapons that will destroy everything in its wake The big drawback of OGame is the speed - the servers are either overloaded or the bandwidth is reserved for those paying users.
OGame is a fun interplanetary game that guarantees you'll always have opponents to play against although you may find it very sluggish.