Here, in case people are interested: http://people.csail.mit.edu/mrub/VisualMic/ http://people.csail.mit.edu/mrub/VisualMic/ I saw a talk on this recently by

Here, in case people are interested: http://people.csail.mit.edu/mrub/VisualMic/ http://people.csail.mit.edu/mrub/VisualMic/ I saw a talk on this recently by Prof. Bill Freeman, a co-author of the above work. The visual mic idea is based on a general technique for amplifying small motions; the motions here are the tiny movements of the bag. The more generic idea is here: http://people.csail.mit.edu/nwadhwa/phase-video/ http://people.csail.mit.edu/nwadhwa/phase-video/ It seems like it could have applications to lots of areas.