  We study the transient response of a colloidal bead which is released from
different heights and allowed to relax in the potential well of an optical
trap. Depending on the initial potential energy, the system's time evolution
shows dramatically different behaviors. Starting from the short-time reversible
to long-time irreversible transition, a stationary reversible state with zero
net dissipation can be achieved as the release point energy is decreased. If
the system starts with even lower energy, it progressively extracts useful work
from thermal noise and exhibits an anomalous irreversibility. In addition, we
have verified the Transient Fluctuation Theorem and the Integrated Transient
Fluctuation Theorem even for the non-ergodic descriptions of our system.
