What did you build that's not meant to be a toy or model, but to serve a general household purpose?
I made an iPhone stand to let me use it without holding it while it's charging, an iPad speaker amplifier that works, but isn't pretty. I'm considering making a nutcracker for sunflower seeds and pumpkin seeds and an iPhone stand for use with the magnification feature (good for looking at Design IDs in tiny font on parts) or to use in lieu of scanning a receipt.