In my '99 Corolla, there is a blank piece of plastic above the radio in the center console where a clock would have been in a different trim level. I noticed during stereo installation that the plug for the clock was still present, and that an unswitched 12v supply was present. As the cigarette lighter is inconveniently located under the drink holder, I thought this would be a good place for a 12v-USB charging connector for mobile device charging. A newer radio install added a rear-mounted USB port and an AUX in port, so I decided to replace the panel with one that would snap in place where the old one was, but offer ports that I needed. I chose USB ports that transferred insertion force to the panel they were mounted in, and paid a ridiculously high price for them. The 3.5mm/1/8th in audio jack for AUX in was far more reasonable. Both connectors had the advantage of having very specific measurements for their needed cutouts online. Photos show an earlier prototype.
This is a significant model for me because it's the first time i created a real-world item from scratch in a modeling app, modified it, and then printed it with all the correct dimensions.