This might cost you quite a few bells to the Nook Brothers for this one, but it's well worth it! This heat changing mug from Paladone isn't like most! It doesn't just change colors, or add a character... the entire image changes!
When cold, the mug is black with colorful outlines of characters and items. When filled with a hot liquid, it changes to a square grid pattern with lots of pictures of your favorite characters!