[AndrewC]

I seem to remember reading that attaching a solar sail to an asteroid would actually be a more effective means of deflection.

An asymmetric assembly of bovine creatures facing in the same direction should prove adequate to the task.

[SteveH]

An asymmetric assembly of bovine creatures facing in the same direction should prove adequate to the task.

Finally, a constructive use for DU has been discovered :-).