I'm a fan of Zachtronics games, though I haven't "beaten" any of them yet. These are my notes as I work through Shenzhen I/O, which is a game that centers around programming various microchips.
Although I'm a professional programmer, I've never excelled at coding puzzles under any kind of time pressure. I'm hopeful that I can exercise this part of my brain and get better with practice. It's a skill that I don't use much day-to-day, but it is fun!