Public transports. The commodity which people rarely use nowadays but every time you board one you fall in love with a totally new stranger.
I think that concept of public transport is receding very quickly. The government is trying to redesign the concept of public transport by implementing AC buses and such to make more people travel by buses and I totally support that. In fact, I think more people should take public transports. Apart from the entire environmental conservation thing, it also gives you a chance to see pretty strangers who you begin to like which in a way promotes world peace or something, possibly.