Too many to list, and a few I do not possess, lol. I will list most of the 51's I possess for the enhancements mostly....
Alright, I IoDA'd one helm....AFTER I obtained the original honestly, because I needed the enhancement for support characters, because I had several IoDAs to spare and could "waste" it if desired, lol. You don't need the IoDA version, showing you the available enhancement, although get the other five.
Two of these, the Oblivion Blade of Nulgath (Rare) and Nulgath Challenge Pet, require an IDoA, although it's worth it if you get a 40,000 AC package for $99.95.