Certain exemplary embodiments comprise a seal assembly, a mandrel, a front module, and/or a rear module. At least one of the front module and the rear module comprises a mount hub, a seal assembly, a chassis, and/or a mount plate. Various annular sealing assemblies can be mounted and dismounted to and from the mount hub. The mount hub can provide substantial central support for the sealing system. The chassis can be constructed to couple the mount hub to the seal element. The mount plate can be constructed to couple the module to the mandrel. The modular pipeline pig is substantially modular. Certain exemplary embodiments provide for relatively rapid mounting and dismounting of elements to and from the module assembly. In practice, such embodiments allow for quickly and easily configuring a pigging system for many different applications.