I think I just had my best game, not because of my awesome score (though that does help), but because I picked up a hero I never had played before and had some of the sickest saves I've ever seen. Just went 3-0-29 as Janna, in a 30min game (was queueing with four other friends), I picked Flash and Teleport, not really knowing what summoners to go with her. Early on, we got dominated by a Garen and Morde, but they got a bit greedy after my team started 0-8 and started tower diving like motherfuckers. I must have saved my teammates on 15 different occasions. Every one of her spells has some sort of support utility on it, which makes her useful in almost all situations. My favorite was a save on my friend who was playing Rammus. He was at about 100hp, got ignited right as he was running away with Powerball. I flashed to him as he was running away over a wall and shielded him. He got away with 7hp. By late game, they had evened it out enough with their stupidity, then their complete lack of CC made them useless (I don't think they had a single stun between Akali, Garen, Morde, MF, and Soraka).
Was fun.