It lets me see how new filament behaves on their first and last layers quickly. I can use it to adjust z-offset, flow rates, etc. Afterwards, I'll know what to expect on larger prints as well.
good color reference. If you want, you can write on it to record info on your filament (brand, color name, specs, price, etc.)
If you make enough of them (and I have), you can shuffle them like a real deck of cards, and even practice cardistry with them. Pretty fun :)
Melt_Burn_Make
