Generically? Probably
http://wiki.project1999.com/Journeyman%27s_Boots
The answer depends heavily on the class and the era and the level.
http://wiki.project1999.com/Eye_of_the_Rigtorgn is pretty hilarious on a level 46 SK
Necros just get too many good clickies.
http://wiki.project1999.com/Holgresh_Elder_Beads
http://wiki.project1999.com/Shissar_Seance_Staff
http://wiki.project1999.com/Bone_Bra...f_Condemnation
Not to mention free pet haste pants and CoS. Each is a different tool in your toolbox, and if you remove the rarity of the item from the equation and things that are useful at more than just level 46+ I'd probably go with Circlet of Shadow.