oGame A free online space based strategic simulation game. All you need is a web browser. And lots of time and patience. Did I mention time and patience already?
As an intergalactic emperor you have the possibility to strengthen your influence throughout the galaxies by numerous strategies. Beginning your rulership at your homeworld you begin to build an economic and military infrastructure with your ressources. Researching new techniques and upgrading your buildings and researches gives you access to superior technologies and improved weapon systems. During the game you have the option to colonize planets and creating alliances with other emperors. Trading with other players and fighting against enemy empires help you to get the ressources you need to prosper even more quickly.
The instructions are in some alien language.
Klingon?