I got most of my inspiration from Kathy Sierra and Why the Lucky Stiff. They're waaaay better than me in this regard, but they taught me that most brains love a little whimsy. I try to add a little since systems engineering can slip into dryness pretty quickly if you're not careful.
Little jokes like the borg cow can lighten things up: https://devopsu.com/newsletters/ansible-weekly-newsletter.ht...
An added benefit is that whimsy helps filter out trolls. Adorable puppies, kittens, squirrels, cows, etc have a way of turning trolls away or at least softening them up a little :)