Ben Grimm (http://ever-lovin.livejournal.com/) doesn't wear any jewelry, yet. He does carry a Star of David however.

Val Von Doom (http://val-von-doom.livejournal.com/) wears a brooch with a stylized representation of Dr. Doom's mask that is the key to her armor. (Not canon but my take.)

Loki (http://seid-shifter.livejournal.com/) wears what ever will make her look fabulous or give her power.