Meet the infantry in New York's volunteer army -- the Good Samaritans who give back

This Thanksgiving, we are grateful for New Yorkers who spend their time putting others before themselves. Oodles of city residents give freely of themselves in infinite ways, but this year's crop of do-gooders use their own unique skills and credentials to improve -- and even save -- lives in New York City.

"Skills-based volunteering is a large, growing trend," said Samantha Warfield, spokeswoman for Corporation for National & Community Service. Retired professionals in particular, she noted, "have a wealth of knowledge they use for a second act."

Below are four notable New Yorkers who have given back in unconventional ways.