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Recently Squire & Hopkins showed that charged dust grains moving throughmagnetized gas under the influence of any external force (e.g. radiationpressure, gravity) are subject to a spectrum of instabilities. Qualitativelydistinct instability families are associated with different Alfvenic ormagnetosonic waves and drift or gyro motion. We present a suite of simulationsexploring these instabilities, for grains in a homogeneous medium subject to anexternal acceleration. We vary parameters such as the ratio of Lorentz-to-dragforces on dust, plasma $\beta$, size scale, and acceleration. All regimesstudied drive turbulent motions and dust-to-gas fluctuations in the saturatedstate, can rapidly amplify magnetic fields into equipartition with velocityfluctuations, and produce instabilities that persist indefinitely (despiterandom grain motions). Different parameters produce diverse morphologies andqualitatively different features in dust, but the saturated gas state can bebroadly characterized as anisotropic magnetosonic or Alfvenic turbulence.Quasi-linear theory can qualitatively predict the gas turbulent properties.Turbulence grows from small to large scales, and larger-scale modes usuallydrive more vigorous gas turbulence, but dust velocity and density fluctuationsare more complicated. In many regimes, dust forms structures (clumps,filaments, sheets) that reach extreme over-densities (up to $\gg 10^{9}$ timesmean), and exhibit substantial sub-structure even in nearly-incompressible gas.These can be even more prominent at lower dust-to-gas ratios. In other regimes,dust self-excites scattering via magnetic fluctuations that isotropize andamplify dust velocities, producing fast, diffusive dust motions.

Simulating the Diverse Instabilities of Dust in Magnetized Gas