I came across this one a couple of hours ago in a sotware support NG I frequent. As a search here established that it does not appear to have been posted here before, I offer it for your perusal (however you define that word).

So this is a story about a very intelligent dog, named
Mace, who belonged to a mechanic. The mechanic was very
pleased with everything the dog did except one thing -- he
ate too much grass. So much, in fact, that their
respectable-looking lawn was turned into a dirt patch unless
the family kept him indoors and only took him out to run on
a leash on concrete sidewalks or dirt paths. So they did,
and the grass grew back to a respectable length, and then a
little longer, so it was like wading to walk across the
lawn. One day the mechanic was out working on his car, and
as he was quitting for the day, he dropped his most
expensive wrench. In the grass. And it was lost. The
whole family looked all over, but couldn't find it. That
night, probably because of all the uproar about losing this
expensive tool, Mace escaped from the house. Nobody noticed
until next morning, when they went outside and found that
all the grass had been chewed down to a respectable lawn
length! And there, shining out in plain sight, was the
wrench! The mechanic turned to his wonderful dog and said:
"A Grazing Mace! How sweet the hound that saved a wrench for me!"