I have one large, overarching project (https://couchmate.com) that I've had for the past 8 years.

Along the way, I'll take little detours into different projects as an escape from the main one, to keep things fresh, explore new technologies, etc. An example is I needed a better way to manage my Twitter lists, so I built Twitlistr in a week (https://twitlistr.com) to explore Nextjs/Next-Auth/Twitter API/Vercel.

I have a huge backlog (~10) of side-side projects I've started but stopped 30-50% of the way though because I got bored.