For the last several years I loved using a squirt of Method Floor Cleaner in my mop bucket; I alternated between bottles of lavender and lemon-ginger. But I haven't seen it at Target in months, and out of necessity have come up with something I love far more.
Oh, this is so delicious.
In my mop bucket I do a tiny dab of dishwashing liquid, then three or four drops of peppermint essential oil. Cleaning heaven.