Crazyglue for most softies will not work, as soft corals tend to shed off too much mucus or simply retract tissue. As Jason mentioned above, it all depends on what your fragging. I use blades to slice muchrooms, epoxy to anchor branches of stony corals to base rock, elastic bands to hold down gorgonian mats or green star polyps, pierceing holes of base rock for thin branch corals such as gorgonians or sea whip, nylon and thread for sinularia and leathers, crazyglue for hard and sps corals, and strong current and pieces of base rock for other situations. There are many ways to frag corals, the most important thing is to be sure of what your fragging- thus this will let you use the best method for the job.
cheers, Rich