Event-driven molecular dynamics is a valuable tool in condensed and soft matter physics when particles can be modeled as hard objects or more generally if their interaction potential can be modeled in a stepwise fashion. Hard spheres model has been indeed widely used both for the computational and theoretical description of physical systems. Recently further developments of computational techniques allow simulations of hard rigid objects of generic shape. In the present paper we will present some optimizations for event-driven simulations that offered a significant speedup over previous methods. In particular we will describe a generalization of the well-known linked cell list method and an improvement on the nearest neighbor list method recently proposed by us. © 2010 Elsevier B.V. All rights reserved.