There are literally thousands of games on Valve's Steam service, and a growing number are small, independent titles. You've probably never even heard of many of them, but for the tiny teams (or sometimes individuals) behind them, their success or failure can be literally life-changing.

Take Lunar Flight, for example.

The game, developed solely by independent Sean Edwards, was released last year, and while it wasn't exactly a blockbuster, it did get a bit of coverage, including a few posts here on Kotaku.

It's coming and going might not have meant much to you, maybe nothing at all if it didn't interest you, but to Sean it meant the world. Or, to put a figure on it, $200,000.

We know this because Sean has done something rare, at least when it comes to Steam games, and disclosed concrete sales data for his game.

Admitting that with sales dwindling "this may be the end" of the game's commercial lifespan, he says that in the 16 months since its release, he's sold 50,000 copies of Lunar Flight, resulting in $200,000 in revenue. As he says, considering the game's niche focus - it's a hardcore simulation of landing a spacecraft - "This is a pretty good result considering my original sales estimations and the game has gone on to become something much bigger and better than I had ever hoped I would be able to achieve".

After taxes and duties and other related payments, he says he personally cleared $100,000. Breaking it down further, he writes:

When I am not having a sale, the daily sales average around 5 - 10 copies, this generates about $100 out of that I make about $50. $350 a week, $1400 a month. This is much less than I would earn if I had a day job, it would be a nice supplementary income. While there will be future sales, they will be less frequent and be harder and harder to promote. When a sale is not on the front Store page as a Daily, Mid Week etc... it's sales are based on discovery where it is burried among the many Simulation tiltles so despite being on sale the revenue increase can be much the same as the average.

So based on this forecast I have to plan for the future and that future is most likely going to be planning for a new title or getting employment.

One thing that's really interesting is that he says the bulk of it "was earned from Sales where it was heavily discounted often at 75% off".

While the post does have a certain finality to it, it's important to note - and this is especially the case here, since he'll be promoting the game at PAX Australia, has just added multiplayer and will be releasing Oculus Rift support in the future - that no game truly dies on Steam.

They just hit a point where it's time to say goodbye.

The Future For Lunar Flight [Steam]