  We describe a quantum computer based on electrons supported by a helium film
and localized laterally by small electrodes just under the helium surface. Each
qubit is made of combinations of the ground and first excited state of an
electron trapped in the image potential well at the surface. Mechanisms for
preparing the initial state of the qubit, operations with the qubits, and a
proposed readout are described. This system is, in principle, capable of
100,000 operations in a decoherence time.
