An idea too simple or too inefficient to work detectably? Obtain
molecules that readily go into suspension (colloids) that are
comparatively flat, like graphite pieces, but which slide
comparatively easily sideways when in contact with each other. A
flask of these should produce heat from casimir attraction when
meeting flat sides together, yet separate laterally eventually by
brownian forces. Just a wild speculation.
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/