  Accelerated expansion of the Universe may result from an anti-frictional
force that is self-consistently exerted on cold dark matter (CDM). Cosmic
anti-friction is shown to give rise to an effective negative pressure of the
cosmic medium. While other models introduce a component of dark energy besides
``standard'' CDM, we resort to a phenomenological one-component model of CDM
with internal self-interactions. We demonstrate how the dynamics of the
LambdaCDM model may be recovered as a special case of cosmic anti-friction.
