  We provide boundary conditions for three-dimensional gravity including
boosted Rindler spacetimes, representing the near-horizon geometry of
non-extremal black holes or flat space cosmologies. These boundary conditions
force us to make some unusual choices, like integrating the canonical boundary
currents over retarded time and periodically identifying the latter. The
asymptotic symmetry algebra turns out to be a Witt algebra plus a twisted u(1)
current algebra with vanishing level, corresponding to a twisted warped CFT
that is qualitatively different from the ones studied so far in the literature.
We show that this symmetry algebra is related to BMS by a twisted Sugawara
construction and exhibit relevant features of our theory, including matching
micro- and macroscopic calculations of the entropy of zero-mode solutions. We
confirm this match in a generalization to boosted Rindler-AdS. Finally, we show
how Rindler entropy emerges in a suitable limit.
