  We propose that stretched horizons can be described in terms of a gas of
non-interacting quasiparticles. The quasiparticles are unstable, with a
lifetime set by the imaginary part of the lowest quasinormal mode frequency. If
the horizon arises from an AdS/CFT style duality the quasiparticles are also
the effective low-energy degrees of freedom of the finite-temperature CFT. We
analyze a large class of models including Schwarzschild black holes,
non-extremal Dp-branes, the rotating BTZ black hole and de Sitter space, and we
comment on degenerate horizons. The quasiparticle description makes manifest
the relationship between entropy and area.
