In snooker it is possible to score more than 147 in a single break. If your opponent fouls before a ball is potted, and snookers you on the 165 remaining reds then you can claim a free ball. now you have sixteen reds and a total of 155. Never achieved in competition but has been in practice/demonstration games. Jamie Burnett, in 2004, scored 148 in tournament play. I think my old club in West London recorded higher score at 151 which used to be listed but isn't shown any more