John Ilhan (born Mustafa İlhan; 23 January 1965 – 23 October 2007) was an Australian businessman and philanthropist. He was best known as the founder and owner of Crazy John's, a mobile phone retail chain. He founded the company in 1991. In 2003, he was the richest Australian under the age of 40. After his sudden death, his wife sold the company to Vodafone.