Can you seriously travel with no luggage at all?
Yes you can.
I've done it. Traveling with no bags is gloriously liberating. You move fast, close to the ground, spontenously. You feel unleashed, undefined by your possessions. It is just you and the world. I am convinced that with less stuff to manage you think different. You learn lots, fast.
I've done a few very short trips this way, and once I took a month-long journey in Sri Lanka without baggage. I would not want to travel this way all the time, but once you go with none, it is much easier to go with very little. It's one of the oldest truism in the world: the less you travel with, the more you take back.
There are four modes of no-baggage travel these days:
Tales of a Luggage-Less Traveler