(ABC News) -- While the shootings at Sandy Hook Elementary School have no doubt left the nation shaken, they have also inspired an outpouring of acts of kindness from across the nation and around the world.
The central hub of many of these is on display in the U.S. Post Office in Newtown, Conn., a community shaken by the killing of 20 children and six school staff members by 20-year-old Adam Lanza, who also killed his mother and shot himself.
Mountains of mail and packages are flowing in from all over the world. Some are simply addressed to "Newtown" or specific families who lost people in the shootings. They're coming with return addresses ranging from Idaho to Virginia Beach and far beyond.
"I think I saw Brazil, Australia, (one addressed to) 'Anybody in Newtown who needs a hug.' It is just amazing," said a postal employee in Newtown.
In the town hall, donated toys are piling up just in time for Christmas.
Kindness is even flowing from victims of other tragedies like Hurricane Sandy, who sent hundreds of teddy bears to hand out to children in the community.
"We've had so much help, we wanted to pay it forward and try to help somebody else," one woman said.
Now, Newtown is hoping people everywhere "pay it forward" in their own communities, with the memory of those lost in the shootings serving as inspiration.
It's a concept that seems to be spreading across America.
In Michigan, a secret Santa of sorts paid off everyone's layaway items at a store there.
Reports are streaming in on Twitter from around the nation of others receiving coffees or meals paid for anonymously by others.
In New Jersey, Kristen Albright told ABC News she found an anonymous card in her shopping cart at Target, where she had gone to buy ingredients for holiday cookies.
She looked down, and found a gift card to Target inserted into a greeting card that asked her to pay it forward to others, in honor of Newtown shooting victim Catherine Hubbard.
"It really made me stop. I was frozen. It made me think about that little girl," Albright said.
Inspired, she did what the card asked, and gave it to a bank teller at the other end of a deposit she was making. Albright says her 11-year-old son Jackson has begun randomly giving now too.
"It really made me think of the bigger picture and family and friends, and extending that kindness to strangers as well," Albright said.
Stacey Jones of Surprise, Ariz., wrote ABC to say she too has been inspired.
"I went to Target, purchased two gift cards, put them in separate envelopes along with the message and handed them to strangers as I exited the store and entered the parking lot," Jones said. "It really felt good to do a small kind deed for someone."
Nicole Reyes of Boston had never heard of the growing movement of kindness when she found a ziplock bag tucked underneath her windshield on her way to work this morning. Inside, she found a Christmas lollipop with a note on a Christmas card that said it was, "In memory of Emily Parker, 6." And urged her to "Pay it forward!"
"I took a minute to remind myself of how amazing it is that a community and entire nation can come together in the wake of such tragedy," Reyes said. "I ran into my house to show my mother the note. After reading it she immediately started crying. It was a special moment for her and I."
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