CG>fill them with water and place the plastic lid snugly atop. Place
CG>them on your window-ledge.
  And then watch the ledge collapse under the combined weight of 8 or 10
  10# cans. :-)
CG>with a counter-argument, but I don't really think they'll absorb
CG>much heat if you place them on a counter.
  Nor in a huge puddle on the floor. :-) I used to fit big sheets of a
  polyurethane foam insulation (Celotex) into the windows on cold
  nights. This made a significant contribution to our nighttime comfort
  and heating bill, and was easily removable the next morning when the
  sun was shining. On exceptionally cold days, they stayed in. (And on
  the north side in a cold bedroom, they were taped in for the winter.)
  The downside was continually moving the residents of the windows, my
  plants, back and forth. But they required some protection from the
  cold, in any case.
  In the summer, those sheets kept the early morning sun from raising
  the temps in my sunny kitchen to unbearable levels early in the day.
  There was a 20*F difference in the kitchen between shaded and
  unshaded.
  I much preferred these sheets for controlling temps in the windows. I
  tried 40-gallon recycled drums, painted black and filled with water,
  in my attached greenhouse. After just a couple of years sitting on the
  soil (mistake #1 - put a cement slab or other vapour barrier
  underneath), those barrels rusted through, and watered the greenhouse
  unexpectedly. They were most effective in lengthening the season at
  either end, but not very good in winter, since the sun was too weak.
                      ...Sandra...
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 * QMPro 1.52 * Grub first, then ethics.
--- WILDMAIL!/WC v4.12 
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