Good news for all of you philatelists, herbivores and compulsive card mailers out there. Just in time for the busy holiday mailing season, PETA has unveiled it's latest star-powered animal advocacy campaign. The limited edition stamp series featuring twenty of the world's most famous vegetarians is on sale through December and possibly January. 

You're sure to see some familiar faces like Pamela Anderson and Natalie Portman, who have been loyal PETA Spokesladies, but did you know that other big names like Ellen Degeneres, Paul McCartney and Russell Simmons also choose not to eat meat? Even historical figures like Leonardo Da Vinci, Ghandi and Johnny Appleseed are featured posthumously.  

Pamela Anderson and Bob Barker were at the unveiling in Hollywood earlier this month. 

Check out some quotes from the stars themselves as to why they choose to become vegetarian or vegan. 

Ellen DeGeneres: "I personally chose to go vegan because I educated myself on factory farming and cruelty to animals, and I suddenly realized that what was on my plate were living things, with feelings. And I just couldn't disconnect myself from it any longer."

Pythagoras: "For as long as men massacre animals, they will kill each other. Indeed, those who sow the seed of murder and pain cannot reap joy and love." Pythagoras recognized the derogatory effects of eating meat a few thousand years before the rest of the world, declaring, "Men dig their graves with their own teeth, and die more by those instruments than by all the weapons of their enemies."

Cesar Chávez: "I became a vegetarian after realizing that animals feel afraid, cold, hungry, and unhappy like we do. ... It was my dog … who led me to question the right of humans to eat other sentient beings."

Sir Paul McCartney: "If anyone wants to save the planet, all they have to do is just stop eating meat. That's the single most important thing you could do. It's staggering when you think about it. Vegetarianism takes care of so many things in one shot: ecology, famine, cruelty."

Leonardo da Vinci: "If you are as you have described yourself the king of the animals––it would be better for you to call yourself king of the beasts since you are the greatest of them all!—why do you not help them so that they may presently be able to give you their young in order to gratify your palate, for the sake of which you have tried to make yourself a tomb for all the animals?"

Natalie Portman: "Eating for me is how you proclaim your beliefs three times a day. That is why all religions have rules about eating. Three times a day, I remind myself that I value life and do not want to cause pain to or kill other living beings. That is why I eat the way I do."