I was looking for a butter dish without any sort of annoying groove, just a flat surface at the bottom, but never found one. I made a simple model that fit my need and I'm very happy with it!

It comes in 3 common sizes here in canada (I don't know about other countries) : 1lbs (454 g), ½ lbs (250 g) and ¼ lbs sticks (125 g)

If you want to wash it in dishwasher, use high temp filament, PETG is not resistant enough, you should use ABS, ASA or PC for example

I have tested it with PC at heavy duty cycle and it is ok.