thinking about this for about 15 minutes, I came up with this idea: using a magic marker, draw a vertical line on one narrow end of the mattress, and a horizontal line on the other. After six months, the vertical line (say) will tell you it's time to flip it vertically end-to-end on the narrow axis. This will reveal the horizontal line, which tells you to rotate the bed 180 degrees lying on the same surface on which it currently lies. This will in turn expose the vertical line, which when followed for the second time will complete the four possible surfaces on which you can sleep.
posted by Eduardo Santos
January 6, 2010
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