NASA is using Fiber-optic stress and strain gauges to evaluate dynamic loads on wings and other aerodynamic surfaces. (paid subscription required)
In addition to being lower profile than conventional strain gauges (see pictures) the technology looks likely to be small enough, light enough, and unobtrusive enough so it would be embedded in aircraft for real time structural health reporting.
It could also be used as a part of a wing that actively changes its camber, a “son of the mission adaptive wing” that NASA tested on the F-111 over a decade ago.