Tachyon the Fringe is on sale for 50% off ($5 USD) on Steam currently through the 26th as part of the Steam Summer Sale.
Steam Link:
http://store.steampowered.com/app/32760/For those that haven't played it...
Tachyon is a mission based free roam space combat sim, much in the vein of FS2. It was also released in 1999, like FS2, and played across the world on every continent. At it's peak it boasted 64 player servers and join in progress across all games.
You have a wide variety of ships, ship upgrades, interchangeable weapons, a unique & fast flight model no other game has copied still to this day. We have giant capital ships, and even larger sprawling multi-part bases.
Single player is composed of two separate story branches based on choices you make and locations you visit open up additional missions and have some impact on how well you will be equipped at the end. Each branch is worth about 14 hours of game play. Your main character is voiced by Bruce Campbell, of Xena, Evil Dead, Burn Notice, etc fame... so expect lots of snarky commentary.
Multiplayer consists of two modes. Base Wars and Arena (deathmatch). Base Wars is a multi sector team based, race / combat / gathering contest to see who can protect and level up their respective bases - unlocking weapons and ship upgrades along the way, until you unlock weapons that can destroy the enemy life support plant. Arena is largely free for all most of the time.
Between the original modders and the FringeSpace project, we've released over 90 sectors of maps for the game. We've continue to host servers round the clock, support weekly games, and provide mod packs so you can fly any of the other fighter class craft in the game.
So if you've not experienced Tachyon and wonder why those crazy FringeSpace mod people are still die hard fans after 12 years, now is as a good a time as any to grab a cheap legitimate copy off Steam.