He was the firstborn son of the banker and philanthropist George Gund II, who made his fortune as the head of Cleveland Trust when it was the largest bank in Ohio. The younger Gund inherited his father's vast wealth and his abundant eyebrows, but he only flaunted the latter. "He loved them," Melanie Blum, a longtime assistant to Mr. Gund, recalled. "When he was going through chemo, he was worried he was going to lose his eyebrows. But he never did, and he was so happy about that."

Mr. Gund died on Tuesday at his home Palm Springs, Calif. He was 75. The cause was stomach cancer, which had metastasized, Ms. Blum said.

He had many successes as a businessman, but he hardly followed a conventional route. He was kicked out of prep school (he got his G.E.D. instead), he enlisted in the Marines, he put off getting his college degree (forever), and he spent his adult life in a kind of alternative study program that could also be called doing whatever he wanted to do — and doing it quite well.

"We did see him as a bit of rebel," his brother Geoffrey recalled in an interview. "If there wasn't a quality about George that was so winning, we might have regarded it differently."

He immersed himself in hockey and high art, independent filmmaking and American Indian history, cowboy poetry and Japanese calligraphy. If he went to Eastern Europe in the 1970s to scout a player for one of the hockey teams he owned, he might slip out with copies of a few low-budget films he would then screen at one of the endless film festivals he helped finance. If he agreed to meet you at noon in San Francisco, he might get there at the right time but not necessarily on the right day.

But he did get plenty done. With his brother Gordon, he bought the Cleveland Cavaliers basketball team in 1983 and sold control of it in 2005 at an enormous profit. The pair bought and sold several professional hockey teams, including the Minnesota North Stars of the National Hockey League, and they were instrumental in bringing the N.H.L. to the Bay Area through their purchase of the Sharks, an expansion team, in 1990.

He was an early supporter of Mr. Coppola (they shared a Mitsubishi turboprop for a time), he was heavily involved at Sundance (Robert Redford ribbed him for his famous mumbling speaking style), and he was a trustee, like his siblings, of the George Gund Foundation in Cleveland, created by his father in 1952.

George Gund III was born on May 7, 1937, in Cleveland, the oldest of six siblings. His mother, the former Jessica Roesler, died in 1954; his father died in 1966. Mr. Gund attended college but did not graduate.

He is survived by his wife, Iara Lee, a filmmaker; his son, George Gund IV; two grandchildren; his brothers Gordon, Graham and Geoffrey, who is president of the Gund Foundation; and his sisters Agnes, the former president of the Museum of Modern Art, and Louise. His son Greg died in a plane crash in Central America in 2005. Two previous marriages ended in divorce.

"He had a lot of money," Ms. Blum said of her boss, "but that was never what you thought of when you thought of George."