My favorite is from the anime after they rescue gaara and are getting ready to head back. When Gai puts kakashi on his back and then it shows Lee bending over and asking Neji to get on his back.
Obviously the one in my signature but I also like these two:
"You never did get it, a real ninja is one who endures no matter what gets thrown at him. ... Let me explain something to you, there is only one thing that matters if you are a shinobi, and it isn't the number of jutsu you possess. All you do need, is the guts to never give up."
"I want to obtain all the jutsus and gain a true understanding of everything in this world. The first one to mix blue and yellow called the new color "green". I want to do something similar to that. If blue is the chakra, then yellow is the seal, and green is the jutsu ... just as there is no end to the variety of colors, there are so many thousands ... tens of thousands of jutsu in the world as well. But in order to obtain every possible jutsu and truth, it would require an eternity. Only one who understands everything after spending such time on this can be fittingly called the Ultimate Being."