When I started working on Memo, I've been working on long-running projects in PHP and Python, and I just really wanted something small, fun and JS to play with. I decided to write a simple game using the finite state machine design concept. I always thought it's neat, but never had a chance to actually use it for anything.
Originally I wanted to build everything from scratch, but in the end I opted to use the approach outlined in the Smashing Magazine article The Rise Of The State Machines, written by Krasimir Tsonev.
Overall, it was a neat project that let me try a lot of different things: ES2015 features, flexbox implementation details, events and states. My favorite was the color and image randomization - picking "pretty" colors using HSL is so satisfying.
My least favorite was getting the Fontawsome icons to show up, which turned up to be a classic PEBCAK.