As of the time of writing this, I'm in the middle of writing an emulator, and I've been wanting to make a C++ project that could utilize more of C++'s OOP features, both for fun and for practice. Coincidentally, I just got into playing Chess online in the past week. I think that a Chess engine strikes a perfect balance between not being too easy nor too hard, and writing one will require me to use C++'s OOP features. I'm naming this (yet to be) Chess engine "JulianneChess" because it is a play-on-words "Julie and Candy", a masterpiece of an IDM song by Boards of Canada.
https://trello.com/b/6HhXs3nH/julianne-chess
