Different situations, demand different types underware or not...
Myself... I'm a big g-string fan with the matching top, in a push-up format. And this is all my girls' doing. Preferably in a nice green <yes green>

, white is always a winner, black is a standard very good fall back... hmmmmm....
Okay back to reality... As I said, depends on the situation.
If being naughty is on the menu and you want to do it challanging <movies for instance>... trust me, less is better - is the only way to keep it inconspicuous to an extend.
Hey, what can i say. I am a big fan of the female body in the right clothing for the right situation! Don't go slutty, unless that's the theme for the party, but don't cover it up like a nun. Keep to what is sexy and in style with what makes your body look good, or enhances for certain purposes.