same old tighty whitey's i always wear, i only answered this because it was the only thread unread on my "your posts" list.
I never wear any, I have about two pair in case I have to go to doctors appointments and they are lace because I hate the feeling of being smothered. Bra is a different story, if I didn't wear one I would get black eyes when dancing or running. So if a bra can be considered undies I am wearing a baby blue one which is like a camisole showing under my shirt today.