Geeking out for me takes the form of the explainer. I take what someone knows about something and describe how it works and why I find it interesting. My reading takes me all over the place, but I particularly of late enjoy nonfiction on interesting topics.
People find my reading about things like quantum mechanics for entertainment surprising. And my willingness to geek out about it even more so.
Occasionally people remark that I ought to be a teacher. Probably.
Doctor Freelove has a nice ring to it. Unfortunately, a career in academia is more focused on research than teaching. And K-12 teachers get stuck doing too much administrivia and not enough teaching.
My times in front of a classroom were entertaining for me. As campus webmaster at Valdosta State, I would guest teach students how to start their websites for several faculty members. I also taught faculty members how to use WebCT and web design and random of IT topics. In college, one class had me working with 2nd graders and a couple times I taught the whole class about something unprepared off the top of my head. And my mother had me talk about my IT work for career day to several classes.
Opportunities to teach like this are something I miss being in a more administrative position.