Attached Link: The Thread

If you're talking about doing it in Bryce, I did a mini tutorial on using the bump map to put engraved letters on an object, back a few pages.

Otherwise you would have to do it in a modelling program, or using booleans (which would probably be a bit of work). It depends on the look you want.

Come visit us at RenderGods.

Ignore the shooty dog thing.