Abstract: A computer executable "aggregate" task is processed by dividing it into subtasks and distributing the subtasks "on demand" to remotely located subscribing computers via a computer network. The aggregate task originates at a coordinating computer, coupled to one or more peripheral computers by appropriate communications links. The coordinating computer divides the aggregate task into multiple independent subtasks. Each peripheral computer begins to "subscribe" to the coordinating computer's aggregate task by obtaining an "idle time activation program" from the coordinating computer, and then installing the program locally. The idle time activation program which may include a screen saver, activates automatically when the subscribing computer is inactive. Continuing the subscription process, each peripheral computer requests a subtask from the coordinating computer. In response, the coordinating computer distributes different subtasks among the subscribing computers, completing the subscription process.