Monster online game are the creation of Mind Candy, an eight-year-old company based in Shoreditch, a district of London that is home to dozens of other technology start-ups. Few of these hopefuls will make much money. Moshi Monsters are Shoredithc's star turn.

Kids who join the site can choose one of six types of monster. By solving puzzles they can earn the currency of Monstro City, and buy monster treats.