From right now until 1pm (Pacific Time) on Sunday, the 4X-styled strategy title Endless Space is free to download and play on Steam. After that time is up, you’ll be once again cast out into the void of not having Endless Space to play. Unless, of course, you enjoy it enough to buy it.
As luck (ok, canny marketing) would have it, the game will be available at 50% off during the free-to-play period. That translates to $15 USD for the standard edition, and around $18 USD for the Emperor’s Special Edition (which comes with a free cloak and menacing voice, or something).
As someone who reviewed the original release quite positively, I’d say it’s worth a try.