A rail strike is a strange time to realise that your start-up is going to be a success but that was the moment that the founders of BlaBlaCar knew that their company was going to take off. BlaBlaCar is the French online ride-sharing company that pairs people travelling between cities with drivers who have empty seats in their car. When it was set up in 2006, founders Nicolas Brusson and Frederic Mazzella found it difficult