I've got a couple, from my orcish adventures in QFP Part 2: On Hostile Waters and The Frostfur Captives.
The party ranger (with his +4 or +5 diplomacy) was the best shot we had at making the goblins friendly to us, but he blew his rolls badly. A couple rolls at -2 later and I had improved the goblins to friendly. In our fights against other goblins I cemented our greenskin alliance by proving that I could win while only using my 1d4 bite attack to butcher the enemy forces. Because of the strong bond I shared with the toothy little *^&%# we (under my guidance and leadership) were able to avoid any major catastrophes with the full cooperation of our little green guys.
On Hostile Waters:
By this module I had gotten used to charging in and chomping on anything I could find, and when I saw a dirty, slimy slug climb onto our boat I thought nothing of it. One successful critical bite attack later the slug was shaken by my usurpation of the natural order of things ("It's the one supposed to be doing the biting, not you!") and my fighter was doubling over with whatever terrible sickness chomping a poisonous slug gave me.