Looks like Avorion which was promised to be free for life and being done for fun, is no longer going to remain free. It has been Greenlit on Steam and has a downlloadable demo now.
I have the non demo version of Avorion that I downloaded before it had a restrictive demo, and before it got Greenlit. I like this game and honestly think they should get paid for this. I just hate they have to go back on their original plan of it always remaing free.