We present a general technique to implement products of many qubit operator
s communicating via a joint harmonic oscillator degree of freedom in a quan
tum computer. By conditional displacements and rotations we can implement H
amiltonians which are trigonometric functions of qubit operators. With such
operators we can effectively implement higher order gates such as Toffoli
gates and C-n-NOT gates, and we show that the entire Grover search algorith
m can be implemented in a direct way.