Recycled dialogue in the OT
 

If you pay close attention when watching the OT, you'll notice some key words and grunts are repeated, such as the Girly Grunt by the turtles, Bebop's "MAMA!!", and a couple of April's screams. It is clear that these effects were added on by the sound technicians and were not natural. Any others you can think of?

Raphael shouting "Banzai!". It's clearly Rob Paulsen's voice, but it was used in an episode where he wasn't available to supply Raph's voice for the episode, except that one line, which was pre-recorded.

I was about to say the same about the aforementioned "Mama!!" said by Bebop. I love hearing it in episodes where Barry Gordon ISN'T Bebop.

BTW I coined Girly Grunt, pannoni, I expect my $.05 in the mail soon. :P

I seem to recall Rocksteady saying "Hey! No fair" quite a bit.

When his staff breaks Don says, "That was my favorite bo." a number of times

Are we going oft said lines or lines that are obviously reused?

Let's do both, because otherwise this thread will die fast.

I am also pretty sure Raph said, "Try these Sai's on for size!" in more than one episode.

I always loved that the pilot used the phrase "Gun it, April!" several times, and by different characters.

Michaelangelo used to say "Alright bud that's me!" in the early episodes and at least once in season 4, I forget which season 4 episode. And what about "Yow, look out, coming at em!"?

It wouldn't surprise me if Michelangelo's "Cowabunga!" is reused throughout the series

Re-using
 

Yeah, or Leonardo's "Turtles Fight With Honour", or all the TMNT's "Turtle Power".