I got this in an email.....don't know it it's true but it's a good story anyway.......................

Does the statement, "We've always done it that way" ring any bells... ?
The US standard railroad gauge (distance between
the rails) is 4 feet, 8.5 inches. That's an
exceedingly odd number.

Why was that gauge used?

Because that's the way they built them in England,
and English expatriates built the US Railroads.

Why did the English build them like that?

Because the first rail lines were built by the
same people who built the pre-railroad tramways, and
that's the gauge they used.

Why did "they" use that gauge then?

Because the people who built the tramways used
the same jigs and tools that they used for building
wagons, which used that wheel spacing.

Okay! Why did the wagons have that particular
odd wheel spacing?

Well, if they tried to use any other spacing,
the wagon wheels would break on some of the old,
long distance roads in England, because that's
the spacing of the wheel ruts.

So who built those old rutted roads?

Imperial Rome built the first long distance
roads in Europe (and England) for their legions. The
roads have been used ever since.

And the ruts in the roads?

Roman war chariots formed the initial ruts,
which everyone else had to match for fear of
destroying their wagon wheels.
Since the chariots were made for Imperial Rome, they
were all alike in the matter of wheel spacing.

The United States standard railroad gauge of 4
feet, 8.5 inches is derived from the original
specifications for an Imperial Roman war chariot.
And bureaucracies live forever. So the next time you
are handed a specification and wonder what horse's
ass came up with it, you may be exactly right,
because the Imperial Roman war chariots were made
just wide enough to accommodate the back ends of two
war horses. Now the twist to the story...

When you see a Space Shuttle sitting on its
launch pad, there are two big booster rockets
attached to the sides of the main fuel tank. These
are solid rocket boosters, or SRBs. The SRBs are
made by Thiokol at their factory at Utah. The
engineers who designed the SRBs would have preferred
to make them a bit fatter, but the SRBs had to
be shipped by train from the factory to the launch
site. The railroad line from the factory happens to
run through a tunnel in the mountains. The SRBs had
to fit through that tunnel. The tunnel is slightly
wider than the railroad track, and the railroad
track, as you now know, is about as wide as two
horses' behinds.

So, a major Space Shuttle design feature of what
is arguably the world's most advanced transportation
system was determined over two thousand years ago by
the width of a horse's ass. ... and you thought
being a HORSE'S ASS wasn't important!