It is padmasana (lotus pose), hanumanasana (split pose) or sirsasana (headstand).
When I tell non-yogis that I do yoga either they ask "Can you do headstand?", or they ask "Can you sit in lotus pose?", or they ask "Can you do split pose?".
I can talk about each asana at least 10 min, if not longer..........(bad question for those who like to talk themselves.) :)