I'm thinking since a long time about writing programs to complete the Anki experience with some maybe more ludic or simply different kinds of exercises.
I didn't invent anything, and the ideas were gavered aroud many of Internet sites.
I wanted to do my own because most (all?) of them are just not free, or configuable, so I could not put my own data to play with.
And I just wanted to build my own programs: it's funny!