Agglomeration of Dust Particles in the Lab
  Dust aggregates are formed in a laboratory plasma as monodisperse spheres are accelerated in a self-excited dust density wave. The asymmetric charge on the aggregates causes them to rotate as they interact with the sheath electric field or other aggregates The charge and dipole moment can be estimated and compared to numerical models. "Dust molecules", where two particles are electrostatically bound but not physically touching, are also observed. 
Lorin S. Matthews, Jorge Carmona-Reyes, Victor Land, and Truell W.   Hyde
physics.plasm-ph