I have favorite quotes from the actual series as well, althought not as many. I'm in the middle of rewatching the entire series so this list will be uploaded slower.

Kemo:	"Listen Slim, I'm much bigger and much stronger than you, and you only got the jump on me because you snuck up and took me by surprise.  What's to stop me from spinning around right now and knocking your-"
Kaiba:	"Try it and I'll drop you where you stand."
Croquet:	"I beg your pardon Master-"
Pegasus:	"You can beg later, when you're being punished."
Yami:	"Ah! Ryoku!"
Joey:	"S'all Greek to me pal ..."
Mai:	"Please, if this is the start of some friendship rant, just save it. I've heard all your lame speeches before, and from that look on Yugi's face, he has too."
Mai:	"In fact, it was so stirring I almost felt the need to throw up."
Rebecca:	"I'm eight!"
Joey:	"Ya, inches tall ..."
Joey:	"Go Drumsticks!"
Mai:	"Uh guys ...Joey named his chicken ..."
Joey:	"It's a Newatari, Mai!"
Joey:	"'Kay ...anybody here got a plan?"
Yugi:	"Yeah, get past those tanks!"
Joey:	"Ya gotta plan B?"
Joey:	"Hey, what's with the turbulance!?"
Tristan:	"Yeah, some of us like to sleep past 5!"
Suit:	"Is everyone OK?"
Tristan:	"You mean besides the whiplash and the sprained ankle?"
Joey:	"Can you say LAWSUIT!"
Tristan:	"So you know these five suits, man?"
Duke:	"Suddenly I feel really underdressed ..."
Duke:	"Why duel yourself?"
Seto:	"Who better?"
Joey:	"Note to self ...don't punch virtual railing ..."
Tea (to Kaiba):	"Look at me when I'm talking to you!"
Kaiba:	"What's this? A cheap old movie projector? Get with the times Noa!"