Surely Arch this has already begun. We have goblets with glass bowls and wood ot metal stems. Metal spinning is another use for a wood lathe. Laminations of copper or brass or aluminum with exotic hardwoods. Check out the WOW site if you are a member and you will see all sorts of combinations and even "flattery" pieces where wood is turned and finished to emulate bronze or ancient ceramic textures. All of these extensions to the basic craft are available and being used by wood turners who like to push the limits. One day i might be good enough to go that route but in the meantime ......... practice, practice, practice