I've compiled a list contain every sci-fi browser based game I was able to find. If you know of any other games that are worthy of this list please contact me via ryan@retrohive.com to let me know.

Battlestar Galactica: Online is based on the re-imaging of the sci-fi television show, BSG from 2003. The game takes place following the events of the second season. Specifically, this is directly after the Colonials destroy the resurrection only to find they've become stranded with Cylons that even more hell-bent on their destruction.