One man's trash is another man's treasure.

You've heard this saying before, correct? It appears someone - a woman, not a man - took it literally.

A painting stolen 20 years ago was found lying in trash along a street, and now it could fetch up to $1 million at auction.

Elizabeth Gibson didn't know anything about the brightly colored abstract work she spotted on her morning walk four years ago on Manhattan's Upper West Side. Sotheby's auction house will be selling the work next month for the now-widowed original owner.

"I would say it was an appointment with destiny," Gibson said in a telephone interview Tuesday. "I just knew it meant something. ... It was extremely powerful, and even though I didn't understand it. I knew it had power."

It turned out that it was a 1970 painting titled "Tres Personajes" (Three People) by Mexican artist Rufino Tamayo, whose work has soared in value in recent years.