I could be wrong, but doesn't using Straight Snap and Construction Lines accomplish
pretty much the same thing as Ortho constraints? Actually, I find it's more versatile.

In the example, I'm moving the sphere, using the Origin as base marker to
create construction lines in X,Y and Z and at 45 degree angles.

There are many ways to "skin a cat", MoI just happens to have some good all-purpose tools. :-)

Jesse