The actor and comedian was also a collector who had a child's love of toys and props, and his prized possessions included contemporary sculptures, paintings from all over the world, furniture, decorative art and movie memorabilia.
Sotheby's is auctioning off more than 300 items worth about $3 million that belonged to Williams and his second wife, Marsha Williams.
Some of the items up for auction:
Along with the art he loved and the bikes he adored, there's no mistaking that Williams was a sports fan. There are boxing gloves that were a gift from Muhammed Ali.
"It really does give you a sense of the range of his interests and what the person was like," said Richard Austin, the specialist who organized the auction. "There were two sides to Robin. There's the public side, but the private and sort of family side...That's something that you probably only saw if you were in the family or one of his closest friends."
One of those pals gave Williams a poster after the comedian helped him survive a tough shoot.
"Steven Spielberg was working on 'Schindler's List,' obviously an intense, emotional experience," Austin said. "And he would call Robin up to lighten the mood, and Robin would just do routines over the phone to get Steven through this very arduous film shoot."
Sandy Kenyon got a behind-the-scenes tour:
There are also reminders that Williams himself was a gifted dramatic actor who won an Oscar for his serious role in "Good Will Hunting."
A portion of the proceeds from the auction will benefit organizations championed by the couple, including Human Rights Watch, the Christopher and Dana Reeve Foundation, Challenged Athletes Foundation, St. Jude's Children's Research Hospital and Wounded Warrior Project. Proceeds from the sale will also help establish a permanent Robin Williams Scholarship Fund at The Juilliard School in New York, where Williams studied before fame came.
For more information, visit Sothebys.com/RobinWilliams. You can place bids online starting Thursday at 10 a.m.
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