D is for Digitize speaker Dan Reetz and a buddy are doing some pretty neat things with cameras. Scroll down to watch them focus a camera after the fact — i.e. see through stuff.
Neat stuff. I’m surprised this hasn’t been done with visible light before. Phased arrays have been in use for a long time for microwaves (e.g., radar) and sound (e.g., sonar). Back around 30 years ago there was an experimental array of microphones on the ceiling of the Bell Labs Murry Hill auditorium that could pick out a single conversation among all those that were going on in a full auditorium.