Things I know.
Like atomkai said, The Sannin are from a myth where a man named Jiraiay practices toad magic and his wife if Tsunade. He has a pupil (not sure if his name is Orochimaru), who turns even and practices snake magic, and in the end they have some kind of battle.
I forget about tailed beasts but I know they are from some myth in Japan if I am correct.
The names Sasuke and Sarutobi were taken from name Sarutobi Sasuke, the person who was said to be the greatest ninja who ever lived.
Drunken Fist is a real fighting style and people learn to use it while they are sober.(Saw this on some martial arts show.)
I am sure I knwo more but I forget them at the moment.