For my birthday, I went to Wi Spa in Koreatown, Los Angeles.
I am absolutely coming back.
There are three broad areas: a men's area with hot and cold pools and nude saunas, a women's area with the same, and most of the spa is mixed gender. They provide shirts, shorts, and slippers for the mixed gender areas.
It's been great to sweat a lot in two saunas and the hot pool. I did a little exercise in the gym. But the most popular spots seem to be the relaxation spots -- the lounges in front of a television or the Korean and Western style beds.
Some people have brought computers; I'm not that much of a nerd.
I'm about to eat one of my favorite Korean dishes, spicy rice cakes, at a very low table.
Highly recommended!