A few weeks ago I looted a Crown of Hatred from the Plane of Hate. According to the wiki description, this item should have right-click Ultravision.
http://wiki.project1999.com/Crown_of_Hatred
The crown I looted does not have a clicky effect and claims to just have worn Ultravision. Personally I don't notice any change to my vision when I put on or remove the crown.
The item history on Lucy implies that the crown originally didn't have an effect, but when it was added, it was a right-click.
http://lucy.allakhazam.com/itemhistory.html?id=2191
I have found forum discussions that state that the crown should be right-click and even castable on others.
http://www.eqclerics.org/forums/showthread.php?t=5165
Not an earth-shattering bug, but it would be nice if the crown was working as intended.