The fluctuation dissipation phenomenology, in essence, is a relation $A=D/T$ that connects the rate of energy absorption to its diffusive spreading, where $T$ is the canonical temperature. We explain how this relation can be generalized in circumstances away from equilibrium. In [1] we propose a minimal Fokker-Planck theory for the thermalization of mesoscopic subsystems, without having any baths. In [2] the flow of energy from a work agent to a bath is mediated by a "sparse" system whose non-equilibrium steady state has "glassy" features. In both cases we explain how to formulate the fluctuation dissipation relation, and what "temperature" to use.

[1] I. Tikhonenkov, A. Vardi, J.R. Anglin, D. Cohen, arXiv:1210.2607
[2] D. Hurowitz, D. Cohen, Europhysics Letters 93, 60002 (2011)