I used to think this was a staple in any kitchen until I moved out of the house. For as long as I can remember, my mom has had the same wooden mortar and pestel to crush garlic. For all I know, she brought it with her from Colombia, because it took me a few months before I actually stumbled upon one in Whole Foods.
I guess porcelain or stone is more common, but the idea of grinding porcelin/stone agianst itself makes me imagine nails on a chalkboard. Apparently most people use a garlic crusher? Nick had one we used to use before I found my mortar, and I hated it. It's annoying to clean properly, and doesn't break up the garlic enough.
