A great 3D printing idea anyone can do at home is design and print custom mats for their sink. That way water doesn't collect and leave calcium deposits or mold on your counter tops and grouting.

I leave my designs here. They are custom so they may not fit for what you may need.

The mats are 200 x 100 mm. The hole for the faucet is 59 x 59 mm. 22 mm from the back and 19 mm from the front on the faucet.

I recommend printing with TPU (rubber filament).