I still don't have half as much free time on my hands as I would
like to have, but I wanted to point out two Master Of Orion
clones. Freeorion  and Thousand Parsec . The Freeorion
wiki claims that Star Trek: Supremacy is FLOSS as well, but
apart from trademark issues, I could not find anything looking
even remotely like FLOSS.
PS: Totally unrelated, but I want a Pandora and I want it now.
PPS: I assume people on this list can understand the PS ;)