Homebrew World - build out more detail outside of the original idea: tidally locked planet with a large series of gears along the "goldilocks zone" that cities are built on. Start a novel - I have a few ideas I've wanted to build out. This is admittedly the least in progress.

DnD Musical - I have been revamping the idea since it was too close to something existing, but I started a script. Alternate Universe - inspired by ARG projects, the idea is that instead of developing space travel, the government focused on the deep sea, and found...things.