This quartet of mini-washcloths ranges from the simplest garter stitch cloth, to a more advanced openwork cloth.

These ones are knit in various leftover stash yarns, cotton and cotton-blends. But you can knit these out of any suitable blend; try something organic and undyed for a natural-spa look. Or something with a tougher fiber, like hemp, for a sturdy knitted dishcloth.

Updates
Feb 20 2014: To make my life a tinier bit easier, I’m putting all of my free patterns on my site only (instead of here and on my site). Don’t worry, it’s still free! Just click the “available for free” link above.