If you want to know about intrinsic motivation, just look at Terry Fox. He had an idea: He wanted to raise money for cancer research by running across Canada. He would do it by running a marathon a day. He would do it on one real leg and one artificial leg. He was not paid. All donations went to cancer research. In the end he ran 3339 miles in 143 days and had to stop; His cancer had returned.
He did not have a special skill. He was not a stand out athlete. It was his determination, his intrinsic motivation that inspired a nation. He is a Canadian Hero.