I do what Monkeyboy suggested.. mount frags to them.
Actually
saw an interesting use for dead acro branches at a fellow reefers last weekend - He uses them to mount frags too, but slightly different.
The Dead Acro branch can be broken easily, and you end up w/ a flat, round, point of attachment. The Live Acro frag, also has a round, flat base to it, right? So what he does is put some super
glue on the end of the dead branch, carefully dries off the broken end of the live frag, puts a tiny dab of glue there, and then attaches the two. In this person's experience, the glue bonds very well (one surface is completely dry, the other semi, and since they are both glued, it sticks very well). He now has a frag mounted to a 1-2" branch of dead rock... this he can glue, tie, epoxy, bolt, weld, or attach in nearly any other manner (as it's dead), w/o fear of harming the coral frag. As the coral adapts and grows out, it encrusts down the "dead" branch, and eventually comes into contact w/ the rock, grows a base, and does very well.
I hope that description makes sense, I had a hard time understanding it over the phone as well, but once I saw it in his tank, immediatley thought it was a great idea!
- Mac