looking for a space strategy browser game

ACSIS

Of course there are LOTS of browser based space strategy games. But i am afraid i have become a bit picky, so i am asking you guys. The criterias are:

-free to play
-no advantages in gamebalance through any form of cash interaction
-planets should be conquerable
-resource trade between players should be possible

That are the criteria. I looked through a few, namely Ogame (where you can buy darkmatter to gain advantages and neither playertrade nor invasions are possible), Space Pioneers (no unfair advantages and trade but no invasions), Galaxywars (edit:no invasion either) and Space Invasion (has no invasion mechanic either, despit the name, duh).

Any other entries?

Frem

I played Ogame for a while. I'm not aware of any space browser games which fit your criteria. However...

Are you tired of browser-based games that are thinly veiled interfaces for databases? Finally, there's a game that just is a database!

THRILL as you insert your very own row in the "rows" table!
With careful selection of SQL queries, you will soon have three or even four-digit numbers in some of the fields in your row! Other queries may allow you to use those numbers to subtract from rows entered by other players -- all while pushing the numbers in your own row even higher!

As you master the game, you may find that you have inserted not just one row into the game, but several!

MySQL Game

It's shockingly close to the Ogame experience.