Aleks pointed me to this website:
Dream Recorder is the ideal companion of your nights, allowing you to understand better this third of our life spent in bed. Dream recollection, sleep hygiene, curiosity, you will find your own reasons for using this software of a new kind. Nights after nights, Dream Recorder keeps records of your sleep profiles. It provides statistics and give you the possibility to annotate your dream records with notes or keywords. . . .
Dream Recorder uses the difference between successive reconstructed images for computing the quantity of motion (see image on the right). Quantity of motions are reflected by the colored bar graph. High peaks mean motions. Very low peaks are just in the detection noise base level.
Dream periods are lit up by spotlights. Normal sleeps are represented by the dark blue shades. Deep sleeps have no lights nor shading. Night events are displayed under the timeline, here a dream feedback followed by a voice recording.
Seth would love this (I assume).