Recently, I tackled Genetic Algorithms to solve some specific NP-hard problems, and Zero Knowledge Proofs. Now I'd love to pick up Elixir and some frontend development.
I routinely keep a web page updated with all my learning projects, both the ones I did and the ones I'd like to do [1]. I found that it keeps me accountable, plus it might be useful for some.
This thread is a gold mine of ideas to expand it!