Carbon-based nanostructures are promising candidates for nano-electronics due to their natural small scales as well as their mechanical, thermal, and electrical properties. In this talk, I will discuss some issues related to dissipation in carbon nanotubes for use as interconnects under electric stress, as well as non-linear transport and modeling in graphene field-effect transistors. Our approach is based on self-consistent solution of the Boltzmann transport equation in the high field regime within the device geometries, and boundary conditions. We obtain the output characteristics of graphene field effect transistors by using the charge-control model for the current. Closed expressions for the conductance, transconductance and saturation voltage are derived in good agreement with existing experimental data.