John Masterson Burke (1812-1909) led a long and successful life with many prominent friends and business associates, including Russell Sage and the Vanderbilts.
He never married, had no close relatives, and lived in a spartan manner in Manhattan. He left his $4.5 million estate in the name of his mother "for the establishment of the Winifred Masterson Burke Foundation, which is to be a rest home for convalescents..." The inspiration for his idea is unknown. Today, The Burke Rehabilitation Center in the NYC suburb of White Plains, NY is the premier rehabilitation and rehabilitation research center in the world.
A dear and close relation of mine is there right now, post hip-replacement and, if you have any doubts about American medicine, you will not after you see how this amazing place works.
It's interesting to read Burke's 1909 New York Times obit. Annoyed distant relatives came out of the woodwork after he wrote his final will.
Also wonderful to read the Victorian language (eg "will says he gave money to restore health, not for enjoyment") in this New York Times report on his bequest.