Bots have long been used as a way to harness large amounts of idle compute power. But is there a dark side to how they could be put to work?  IoT devices, such as the Nest smart thermostat, are very powerful computers, which are often idle for 99% of the time. If cyber criminals can find a way into a large number of IoT devices and take them over, without the knowledge of the owners, what would the consequences be? Potentially a massive bonnet. IoT manufacturers need to place security at the heart of the design of their IoT devices, and include a way to monitor the IoT activity.