You can hop on a freighter across the ocean, then buy a car, or maybe a motorcycle, travel and then trade it in for a plane ticket when you are ready to move on. You can work your way by sea working on a yacht, or circle most of the world on buses and trains. Price, length of journey, reliability and comfort vary a lot with each mode of transport, so you’ll want to pick the ones which best fit your budget, and itinerary.