Unconventional Computing
Computation can be performed not only by silicon chips and electricity but also by many other things including tinker toys, billiard balls, water pipes, lights and mirrors, vats of chemicals, DNA, bacteria, and quantum mechanical systems. Furthermore, in some models of computation billions of events may take place simultaneously, with or without synchronization and with or without explicit programming. Some of these unconventional models of computing appear to provide advantages over current technology and may serve as the basis for more powerful computers in the future.