The search for Axions and for other WISPs, Weakly Interacting Slim Particles, has recently picked up considerable pace.

Precision experiments looking for WISPs use a panoply of advanced techniques, explore a sector of particle physics outside the Standard Model in and are complementary to accelerator experiments.

In most searches the main signature for WISPs is their interaction with photons: low background, high efficiency photon counters are crucial and is where a large research effort is directed. Other signatures, such as the direct coupling to matter by chameleons, are however also open for exploitation.

We will briefly discuss a panorama of experiments and techniques, concentrating on the CAST helioscope, which uses different kinds of photon counters. It has the potential to be upgraded with new high-performance photon sensors, such as Transition Edge Sensors, and with novel detectors, such as optomechanical sensors to detect pressure from a flux of solar chameleons. These recent developments will de described, along with their perspectives in IAXO, the International AXion Observatory, a next generation solar magnetic telescope already proposed to CERN.