Detectors designed for particle-flow calorimetry at the Linear Collider will feature unprecedented granularity (tens of millions of channels) to reconstruct the "image" of showers and accurately reconstruct them. With embedded ultra low power readout electronics, they allow to design large area smart detectors. Various technologies have been studied over the last ten years, from highly granular Resistive Plate Chambers or MicroMegas and Gems, to Silicon PM scintillating tiles or large area PIN diodes. These "square meter" detectors or their readout electronics with accurate charge and time measurement not only find applications in medical imaging but also in muon tomography for volcano studies (MuRay or TOMUVOL projects), astrophysics experiments (PEBS) and Nuclear physics (HN diffusion). Future perspectives will be also discussed.