That "might" be possible with a script attached to the item, with a EVENT_EQUIP_ITEM and EVENT_TIMER with a random call in it. (similiar to the Jester of Bristlebane behavior). But it would only last as long as the timer, however long that is set to. This is assuming you have the knowledge to create a new item, writing perl or lua, etc. Unless someone else has a better idea. I'm no expert.
