I only have three snakes that are aggressive on days other than feeding day, and I'm slowly working with these snakes. One hisses and tries to strike, one just tries to strike with no warning and the other is actively coming out of her enclosure trying to get me (boa).

Tongs are a must with my snakes. I learned very fast that fingers are not for feeding snakes. I tried dangling a f/t mouse to my corn a few years ago and she let me know, "Hey, those mousy smelling things are warmer than what you are trying to give me. They must be food!" Chomp! She got my finger instead of the mouse. Got me right on the side of my fingernail! Ow! So yea, I quickly got some tongs after that. Only problem is, I swear my tongs are not long enough. They are your standard tongs used for snake feeding. Not sure the exact length but two of my snakes try to by-pass the tongs to get to my fingers.