The five rules of a Twitchhiker: 1. You can only accept offers of travel and accommodation from people on Twitter. 2. You can't make any travel plans further than three days in advance. 3. You can only spend money on food, drink and anything that fits in your suitcase. 4. If there is more than one offer, you choose. If there is only one, you have to take it within 48 hours. 5. If you are unable to move on from a location within 48 hours, the challenge is over ...