Deep Dish Nine is my 2nd attempt at making a game (after Cripple Mr. Onion), and I think it turned out pretty well. You have to pilot a spacecraft around the TRAPPIST-1 system (a recently discovered star with 7 earth-sized planets orbiting it) while delivering pizzas. The goal is to try to make it onto the high-score board by minimizing delivery time and fuel usage.
The game uses a reasonably accurate n-body simulation of the whole system along with a proper velocity-verlet integrator and a reasonably short timestep. The ship, sun and planets all interact with one another, and the planets get randomly initialized within known bounds for the system. Your ship can either use a traditional rocket thruster or a “project orion”-style nuclear propulsion scheme (where you drop nuclear bombs behind you and ride the shockwave), and even loses mass as you use up fuel! To deliver the pizza successfully, you need to get within ‘delivery range’ of the target planet before your time limit runs out.
See it in action here:
You can download the game/source and see a full write-up. You need to rename the *.zip file to *.arduboy to get it to work with one of the package managers. I haven’t tried it with a package manager yet, but in theory it should work fine. Enjoy!