In his wonderful and little-appreciated classic, PROFILES OF THE FUTURE, Aurthur C. Clarke pointed out that there are two kinds of technology, the expected and the unexpected. As illustration, Clarke made a list of "unexpected" technologies. This include X-Rays, nuclear energy, photography, superconductors, lasers, Carbon 14 dating, and others.
I am very interested in the nature of unexpected or unanticipated technologies and would like to acquire a longer list. I'd love to have nominations of technologies that were relatively unexpected. I can't offer a hard definition of unexpected, since this will vary by expertise and time. Clarke defined "expected" as "concepts that have been around for hundreds or thousands of years" before they became real. I would narrow that to say "concepts that have been around for decades."
What technologies were unpredicted?