1. A method of classifying a computer object as malware, the method comprising: at a base computer, receiving data about a computer object from each of plural remote computers on which the object or similar objects are stored or processed; wherein the base computer comprises plural threat servers arranged to receive the data from the plural remote computers and apply rules or heuristics against the data in real time to determine whether or not the object is malware and to communicate the determination to the remote computers; the base computer further comprising at least one central server in communication with the threat servers and arranged to receive the data about objects from the threat servers to maintain a master database of data received about objects from all threat servers.