Plasma particle simulations are performed using GRAPE-6, a special-purpose computer for calculating gravitational N-body systems. GRAPE-6 rapidly calculates the gravitational force between particles using specialized pipeline processors. The peak performance of a unit of GRAPE-6 reaches 985 GFLOPS. We investigated speeding up plasma simulations through the use of GRAPE-6 for the calculation of Coulomb interactions, which have the same form of central force as the gravitational force. As an example of plasma particle simulation using GRAPE-6, we simulated the Buneman instability. As another example of plasma particle simulation, we simulated a Coulomb crystal in a dusty plasma. The formation of a Coulomb crystal was observed under typical laboratory conditions. We found that GRAPE-6 can perform the entire operation of the simulation of a Coulomb crystal with 5 × 103 particles up to 210 times faster than a 1.6-GHz Pentium4 CPU.