Starship Theory, a game that helped to inspire the creation of SpaceSlog is now free over on steam. https://store.steampowered.com/app/574760/Starship_Theory/ (https://store.steampowered.com/app/574760/Starship_Theory/)
There are a few hours of fun to be had, though be warned, the game has been abandoned by the developer and still contains various bugs and little content.
After spending 20some bux on it, this is kinda a kick to the nuts
And now its been released out of Early Access.