  We compute the $T=0K$ Van der Waals (nonretarded Casimir) interaction energy
$E$ between two infinitely long, crossed conducting wires separated by a
minimum distance $D$ much greater than their radius. We find that, up to a
logarithmic correction factor, $E\propto -D^{-1}| \sin \theta | ^{-1}f(\theta)$
where $f(\theta)$ is a smooth bounded function of the angle $\theta$ between
the wires. We recover a conventional result of the form $E\propto
-D^{-4}|\sin\theta | ^{-1}g(\theta)$ when we include an electronic energy gap
in our calculation. Our prediction of gap-dependent energetics may be
observable experimentally for carbon nanotubes, either via AFM detection of the
vdW force or torque, or indirectly via observation of mechanical oscillations.
This shows that strictly parallel wires, as assumed in previous predictions,
are not needed to see a novel effect of this type.

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