Intersecting cylinders.

A friend of mine asked if I knew anything about the following. I have never encountered this object. Does anybody here have a clue or know of a pertinent URL?

Imagine three cylinders (same diameter) which intersect at right angles to each other. If you cannot visualize that, think of the XYZ Axes of a Cartesian coordinate system. Then imagine each axis as the center of a long cylinder.

Any idea of what the intersection looks like? Does anybody know a site which might have a graphic like this?

I am also posting this on the Maths Forum.

It's hard to explain, but it looks a bit like a cube with round edges :)

Btw it would look better if you did it like this: draw a sphere instead of this weird cube :p and have the tubes go only half the way through the sphere... that should be enough.

Oh huh... you're doing this in 3D right? :)