We will discuss the problem of gravitational fluctuations confined inside a finite cutoff radius r_c and outside the horizon of a class of black holes. We find, in the long wavelength limit, a dispersion relation which matches that of a Navier-Stokes fluid. We derive cutoff-dependent formulae for the diffusion constant, as well as thermodynamic quantities including temperature, energy and pressure, and the entropy. We show these quantities obey the first law of thermodynamics under the assumption of radial isentropicity. Our approach does not require AdS asymptotics. Although I will mostly discuss the linearized case as in 1006.1902, I will also touch upon some concerns in the nonlinear generalization.