That sounds fun, how did you get your friend to join you? I learn Tai Chi and also from this year, Yoga, though I know yoga's not really a martial art! Sometimes I practice Tai chi nude in my room, just by myself though. Normally I need more space to do the full performance so I go outside. I did once practice on the beach in just trunks and someone asked me about it in Italian (I was in Italy). It was nice with the lapping of the waves.