I’d note that there are many different kinds of hackathons, which vary wildly in terms of length, ambition and seriousness, so everyone’s answer is going to be

I’d note that there are many different kinds of hackathons, which vary wildly in terms of length, ambition and seriousness, so everyone’s answer is going to be different. At my previous employer, we did 2 hackathons a year. They were structured so that you could go hard on something you cared a lot about if you wanted to, or you could walk around checking out the (often pretty novel and cool) projects that the teams were working on. There was free food, karaoke, one time there was a cover band playing dance music. If you didn’t want to do a hackathon project, you could take a course on Lynda or Pluralsight, or just goof off and hang out. However, it was a sort of “enforced holiday” where normal day-to-day work was halted. Sometimes people would work on an incremental quality-of-life improvement to the product that normally wouldn’t be prioritized, with the goal of actually getting them into the product. I’d usually start teams doing really ambitious projects with lots of whiz-bang stuff with the goal of getting the product folks to think bigger about where our product could go. It was a lot of fun, and I think more companies should run hackathons this way.