The current issue (March 2012, #237) of Woodturning Magazine has an article by Gabor Lacko on the use of resin for creating decoration on a double-skinned bowl. He turned a bowl and glued slices of yew branches to the outside of the bowl. He then filled all of the gaps between the yew slices with casting resin and once that cured he finished turning. I think the end result is quite stunning. There are not pictures yet on the Woodturning website so you will have to pick up a copy of the printed version if you want to see this.
Based on what I learned from our January demonstrator, Stephen Hatcher, I think that West System 105 epoxy would be great for this type of application. Gabor applies the resin to the bowl while it is still chucked so I presume that some type of filler would be necessary to keep the resin from running. All in all, this looks like an interesting project, albeit a stinky one.
Have you tried this type of project? If so, what type of materials/construction did you use and what did you learn in the process?