I'm thinking particularly of the episode "The Mind's Eye" (TNG 4x24). When Picard tells Ambassador Kell that Worf is on the case, Kell interrupts to request another security officer due to Worf's discommendation. ("Worf's discommendation makes that very awkward.")
Kell is from an outlying region of the Empire near the Federation border, so presumably he didn't witness the discommendation firsthand. How then does Kell know about it, if Worf's name is not spoken in the Empire? Presumbly "not spoken" would also extend to the Klingon equivalent of Facebook.
I noticed in the episode "Sins of the Father", "Duras then rips Worf's baldric off of him, telling Worf he is unworthy to wear the emblems of their people.", but it's back on again next episode, so it's not that.
I've searched on Memory Alpha and Memory Beta as well as Google but they have nothing.