Note: I wanted to try Cults3D as a possible alternative to Thingiverse, but after giving it a bit of a look, I'm not super impressed. Feel free to visit my Thingiverse page if they can manage to keep that site running:
I went to school as a mechanical engineer, and got interested in 3D modeling, specifically the SDRC I-DEAS CAD/CAM software system. This interest got me my first job working for a CAD/CAM reseller doing pre and post-sales support. I was lucky to be involved in 3D printing in the early 90s - for a demo of rapid prototyping, I modeled the mouse from my HP-UX CAD workstation and it was rendered via stereolithography. I still have that model, but across the years I stopped using CAD and moved to systems administration. Now that 3D printing is affordable and mostly reliable, I've gotten into it and am having a blast. I printed all the usual cute little trinkets and tchotchkes, but quickly got bored of that. What I find most interesting is needing something, then spending a little bit of time in a CAD program and soon after that having a real, functional version of the part in my hand.
I'm a cyclist and bike mechanic as a hobby and a side job, and have found endless applications of 3D printing to both bikes and bike maintenance. Coworkers have also come to me with many varied requests, each of which has been an interesting challenge and an opportunity to learn.
I am constantly learning, constantly trying to challenge myself to learn new things and technologies, so hopefully as I progress my designs will continue to improve.