Space Invasion

Space Invasion is a text-based online browser game. Space Invasion is a Space-strategy themed game. It currently has over 500,000 Players. Space Invasion was created by the company Bigpoint.
Resources.
There are 4 types of resources. They are:
Pig Iron is for upgrading buildings and also to help create Metal Slabs.
Metal is harder, more resistant and more mouldable than pig iron, and is used mostly for ship construction and better structures. This is the most used substance in the game
Kryptonite is used for almost all types of ships and buildings. It's also used for research.
Spice is a mostly a rare raw material. As a result, it is that much more valuable. Spice provides a good performance in ship drives, in research and also in alloys. Spice even plays a vital role in food production. It is essential for an up-and-coming empire.
In this game you can trade the various resources with the rule of thumb being 6:3:4:1 in the order Pig Iron, Metal, Kryptonite, Spice.
e.g. 6k Pig Iron would be traded for 3k Metal, or 4k Kyrptonite, or 1k Spice.
Mining.
Mining is the first task you start in the game. In order to mine the four resources you must upgrade each mine. Every upgrade increases the amount of resources the mine produces every hour. But every upgrade uses more energy. So accordingly you must also upgrade the Fusion Plant, which produces energy for the mines. 
Every upgrade uses another field. On your first planet there is 240 fields.
Building.
This is the second possibility after mining. You can build and upgrade the Development Center which decreases your building times for factories and such. The research lab unlocks different types of research, and decreases research times. The weapons factory is needed for all ships and defenses. With every level the weapons factory decreases production time.