I’m working on a chess based logic puzzle, which isn’t a game of chess per se.
I’ve completed the game in many languages and frameworks from the original version AMOS Basic on the amiga, to using C with a gaming library called allegro, just as a fun exercise in learning C, to Flash with several frameworks(to learn Flash Actionscript), Python with Kivy(yep to learn some Python), Lua in GiderosMobile framework, partially done in Unity 3d, and Leadwerks, and now finally in UE4 I’m about 20 percent done with the basic piece logic all sussed out now. I only ever released the C version, in a competition and won a prize for it. 
Finally I may have settled into an engine that I can put out the game in glorious 3D, although the 3D pipeline is a weakness for me, not being a modeler.
I’ve also got ideas for some other games I hope to get around to one day, most likely as my retirement hobby, not one for gardening haha.
Enjoying the BP way of doing things although it actually seems harder to do than cutting code, to be honest. (Particularly when you revisit the BP later) Not a fan of C++, and would love to be able to use Lua in this engine some day.
My motivation is simply to see something working on a screen that started as an idea.
Cheers,
Max