In a Dungeons and Dragons 3.0/3.5 Edition (mix of the rules) game that I am currently playing, a series of events unfolded that was simply awesome. I play a human paladin/divine martyr (Solarian), brother to a Psionicist (Isaac). The rest of our party consists of a Halfling Druid (Schan), a Half-elf Bard (Onyx), and a Half-Orc Fighter (Erdrick).
We had been asked by officials of the city we live in to go and examine a ruined tower that they believed was under the occupancy of gnolls. Since we started this game at level ten, we assumed there was a bit more to the adventure than met the eye. So we set off, making good time, showing up right as night was falling. Since I had the Endurance feat, I volunteered to watch throughout the night, making certain that nothing would ambush us, namely the gnolls. When I grew weary a few hours before morning, I took a quick nap while my brother's psicrystal took over.
The night went uneventfully, and the five of us continued into this tower, which immediately showed signs of use. However, the gouges and such that we saw on the walls were far too deep and thick to be made by gnollish paws. Sensing something dangerous in the air, I heartened my companions and continued forward with Erdrick, while the rest followed behind. We found a few assorted beasts in the tower, but nothing we couldn't handle.
Eventually, we came upon a dungeon-looking room with several dead gnolls chained to the walls, their bodies broken and mangled in a way that even made our chaotic evil Bard queasy. (Solarian didn't know about the Bard's alignment). Now with my friends slightly afraid of whatever the source of this damage was, I pressed forward, with Erdrick guarding the rear of the party. As we were entering the next room, the stone door slid shut, and Erdrick and Isaac were cut off from us. Mutated Gnolls started to enter the room, obviously magically tampered with. We fought and finished them off, and I was at -5 HP at the moment. I also had picked up the Die-hard feat, so I was able to stay alive and fighting. In this fight, I had used all of my paladin healing spells and Lay Hands, as did my bard and druid companion. None of us were really built to fight, and the experimental gnolls were quite powerful.
The Druid found the lever which reopened the stone door, and on the other side, we found Erdrick unconscious on the floor, and Isaac conscious, but in no position to do anything. (Before I go further, I should explain the Divine Martyr. It's a player-created Prestige Class, and essentially allows the casting of a minor, medium, or major healing spell at the cost of the same amount of hit points to myself. It basically allows me to 'drain' damage from my fellows unto me.) My channel damage ability is a last resort, but Erdrick was going to die if I did nothing.
I announced my plan of action to my comrades, and instantly, all of them start telling me not to. But being a Paladin, I ignore them, as I believe that Erdrick would allow them to fight their way out, whereas I could not. (The channel damage also has a Fortitude save for half, DC 7+ the amount of damage channeled.) I grab Erdrick (-9 HP by now) by the wrist, and now they are yelling at me to stop. I used my strongest Channel, healing him for 2d8 + 10. I rolled a total of 13 and added the 10 for a total of 23. Erdrick was now awake and conscious, just in time to see me slump over at a whopping -28 (failed the saving throw, hehehe).
Morosely, the party rested and finished off the evil wizard who was experimenting on these creatures. Isaac, my brother, and Erdrick went berserk on him, keeping only his head for evidence while eviscerating the rest of his body for revenge. All of them near death, they marched their way out of the cave, everyone still in a silent, shocked mood over my sacrifice. As they exited, a bright light appeared in front of them, and to everyone's surprise, even my own, I was standing there, fully healed. (This was a surprise to me, because if we die, we're not allowed to make a new character until the current session is done.) Apparently Heironeous, my deity, thought that my sacrifice was highly noble, and granted me a second chance at life. Also, the +2 Bastard Sword I wielded was given several magical abilities.
After rejoicing, we returned to town for our reward. I promptly gave my share to charity, much to the disappointment of the rest of the party. Things had returned to normal. But the concern and almost fear that everyone exhibited was touching and awesome. The dungeon master later told us that had I not done that, our chances without Erdrick would have been far lower. He was also amazed that I had done that, which is why he gave me a second chance. After that session, I gained an extra level over everyone else, which rocked!