It represents the passing of time by shredding the days of the year-- printed on a paper roll-- at a slow constant rate. To shred one day takes 24 hours. There is no 'off'-button. As the seconds pass by, the tattered remains of the past pile up under the device.
If you're interested in manufacturing the Chrono-Shredder, get in touch with Hertrich via her website.
http://www.susannahertrich.com/html/chrono_shredder.html - via ryanyeah