CrazySpence has put together a really cool plugin for the Vendetta Online MMO space sim. His addon replaces the game's native sound with classic tracks from the original Wing Commander game. Download the patch here (8 meg zip). Spence is continuing to work on additional updates to his plugin in the form of an on/off button, different music variation and more in the future.
Although you might hear about Eve Online or Jumpgate more often, Vendetta Online has been successfully plugging along for more than five years! They're currently running a free trial for eight hours of game time and otherwise run $9.99 a month. If you're not able to play right now, you can just listen to the tunes in CIC Music or after purchasing Wing One.
I have created a plugin for the game Vendetta Online that replaces the audio tracks with Wing Commander 1 to pay homage to the greatest game ever. The short patrol tracks can become....tedious when spending long amounts of time flying through the universe but the nostalgia value is quite high especially when engaged in combat to Wing Commander's battle music or when docked with a station listening to the music from The Claw's bar.