A contented cow gives more milk.  This is a fact that has long been known in the farming industry.  And, a well rested cow is a contented cow.  So, one enterprising individual has developed a waterbed for cows.

It seems that the waterbeds are softer to lay on than straw on concrete and provides better support.  And, because the cows are more comfortable, they give more milk.

Of course, whether this is true remains to be seen.  About 30 years ago, some farmer were claiming that putting large magnets on your gas line gave you better gas mileage.