1. A computer system for allocating computing tasks in a computer network, comprising: a plurality of server computers coupled to a communication network, the server computers for sending requests over the network for an allocation of server tasks and processing tasks, the processing task requests having an associated expiration time; the plurality of server computers for receiving the server tasks provided to the server computers in response to the requests for server tasks and for receiving processing tasks within the expiration time in response to the requests for processing tasks; and each of the server computers for performing the allocated processing tasks if there are no pending server tasks.