  Many hypotheses have been raised to explain the famous Fermi paradox. One of
them is that self-replicating probes could have explored the whole Galaxy,
including our Solar System, and that they are still to be detected. In this
scenario, it is proposed here that probes from neighboring stellar systems
could use the stars they orbit as gravitational lenses to communicate
efficiently with each other. Under this hypothesis, a novel SETI approach would
be to monitor the solar focal regions of the most nearby stars to search for
communication devices. The envisioned devices are probably not detectable by
imagery or stellar occultation, but an intensive multi-spectral monitoring
campaign could possibly detect some communication leakages. Another and more
direct option would be to message the focal regions of nearby stars in an
attempt to initiate a reaction.
