It's an especially cool staff to have if you are playing a vampire or a werewolf or some other kind of dark being that would enjoy sneakily collecting people's nightmares like a creep. People say that the Skull of Vaermina is weak, but it can actually be pretty fun once it's charged up. This is the quest from Dawnstar where you either destroy or keep Vaermina's staff. You then reforge them into The Amulet of Gauldur, an amulet worth having as it grants 30+ health, stamina, and magic.
Getting the amulet of Saarthal is also a part of the Forbidden Legend quest, a neat little quest where you collect three amulets from three different tombs. It's a nice staff to have when you are low level and can run out juice in the middle of a battle. I find the Saarthal quest worth doing because I actually like collecting all the magic rings and having the Staff of Jyrik.
I sound petty, but I've always enjoyed summoning Arniel's sorry ass and making him fight for me. Pretty satisfying after the dismissive way Arniel treats you during the first college quest in Saarthal.