Growing up, I would occasionally see semiconductor chips lying around the house (my father studied applied physics and works in the semiconductor chip industry). Being curious, and probably to my dad's disapproval, I would often pick them up and play with them, tracing the lines that formed beautiful patterns across the brittle surface. Having this association with chips, the pictures of flexible, stretchable silicon integrated circuits shown at Symposium X by John Rogers blew my mind, especially the picture of the glass pipet plunging into one without it breaking.
The applications of the ability to print a thin, stretchable layer of silicon onto essentially anything are insane! His research is focused on bio-integrated electronics, where these silicon circuits are printed onto thin layers of tissue. The speaker started by showing a video of thin cardiac sensor tapes placed on top of a pig's heart to sense the heart activity with high spatial resolution. Then, he continues to blow my mind by showing how the sensor tapes can be used to sense brain activity.
Just as I was wondering if it would be possible to have these sensors implanted in our bodies for a longer period of time, the speaker brings up bioresorbable electronics--printing the circuits on silk so that it will be readsorbed into the body. This will allow the circuits to wrap around the human brain much better and sense localized activity. Incredible! This has by far been my favorite talk of the conference so far!