Posthuman Blues

Chapter in progress:

Mainstream SETI avoids another unsettling possibility: that some extraterrestrial radio transmissions may not be signals at all, but templates for actual alien personae. If it's possible to place a self-replicating automated probe in another star system, it could be used as a receiver as well as an observation instrument. Neurologically inclined aliens could "upload" themselves into a computational substrate and "fax" themselves to the distant receiver at the speed of light.

Rudy Rucker deals with this basic idea in his (fiction) books "Freeware," "Realware" and "Saucer Wisdom."