  The search for extraterrestrial communication has mainly focused on microwave
photons since the 1950s. We compare other high speed information carriers to
photons, such as electrons, protons, and neutrinos, gravitational waves,
inscribed matter, and artificial megastructures such as occulters. The
performance card includes the speed of exchange, information per energy and
machine sizes, lensing performance, cost, and complexity. In fast
point-to-point communications, photons are superior to other carriers by orders
of magnitude. Sending probes with inscribed matter requires less energy, but
has higher latency. For isotropic beacons with low data rates, our current
technological level is insufficient to determine the best choice. We discuss
cases where our initial assumptions do not apply, and describe the required
properties of hypothetical particles to win over photons.
