Best part of having an office job with loads of free time in-between actual work stuff

At my current job (public administration) the actual work load is fluctuating. Which means if no new work orders are coming in, there's literally nothing to do. And while other coworkers are sitting around doom scrolling on their phones, playing browser games or chatting while drinking coffee, I like to keep myself entertained by being actually productive in my spare time by either tackling my book pile of shame or building Lego sets to decorate my office with. Anyone want to take a guess...