My son designed a Martian with house and rocket ship in Tinkercad a while back and I printed it out for his birthday. I needed to enable supports to do it, but it worked. His reaction when he saw it was "I wanted it blue". No pleasing kids.
We needed a way to hang a hummingbird feeder in our backyard so I modified Printingin3D's Gothic Shelf and fixed it up.
If you didn't see it I made replacement pull handle for a gas engine. The story behind that was we were renting a rototiller. When using it the string didn't retract and dangled into the tines so I flipped it up and set it on the engine not realizing that engine was going to get HOT. Getting the handle off wasn't any trouble, I remove melted plastic from hot metal all day, but now I had damaged the rental place's tiller. So I asked them if I could make them a replacement. Took some careful measurement and decided it would be best to design it laying down so the layers weren't stressed when it gets used. Looks good so far, I gave the print to the rental place which they're excited to test out for me.
Saw a cool abstract game on Reddit and I made a quick project of printing out. Then I had to print another one of the creator of the game. Still not sure how it plays, tho.
For the modeling project for my work a little laptop was needed and unfortunately all of the ones I found online were not very good for 3D printing, so I modeled my own.
Having a 3D printer is cool.