I was watching some earlier episodes of the anime and realized how awesome of a character concept Haku was. He was young, skilled, had a cool bloodline and could make hand seals with one hand. The fact that he wore an ANBU mask but without the ugly ANBU clothes made him look cool as well. And we all know that androgyonous characters make the best ninjas because they can infiltrate both as men and women. It was also pretty much stated that Haku was stronger than Kakashi at the time but died willingly to protect Zabuza from the blow.
I wonder how strong Haku would have been in the series' current time if he had survived up till now. Would he have been on hokage level or stronger? One of life's great mysteries.