The ending of Tails' story when he decides to stop Eggman from destroying Station Square by himself, complete with townspeople cheering him on.
The ending of Knuckles' story where he is musing about accepting his fate as guardian of the Master Emerald and mentions how he's at peace again.
The entire ending of E-102 Gamma is both this and a Tear Jerker. After a climatic battle between E-101 Beta MK II, he finds that it was powered by a Flicky and as he walks past it, he realizes that his "brother" was actually his husband, the birdie that Amy was taking care of was her child, and that he, or rather the animal inside him, are those Flickies' wife and mother. With this knowledge, Gamma succumbs to the damage he received from the battle and self-destructs, freeing the Flicky and letting her reunite with her husband.
A small one for Sonic. In the last story, instead of simply resorting to sealing Perfect Chaos back in the Master Emerald, he'd rather find another way of putting a stop to him - by wanting to help the creature heal on the inside, help remove the anger the creature has harbored over the centuries.
After being shot down at the end of Sky Chase Act 1, Sonic crash lands back in Station Square and the very first thing he does is worry himself sick over Tails, who was piloting the very same Tornado plane that got blasted down by Robotnik's Egg Carrier. Sonic really does care that much about his best pal.