He claimed to have fathered 47 children, ran up a net wealth of $100million and spent his final years on the run from the law.
Now, computer pioneer John McAffee has been found dead in a prison cell in Spain at the age of 75, with the Catalan justice department saying "everything indicates" he took his own life.
The British-born boffin made his millions developing the first commercial anti-virus software, but fled authorities chasing him over tax evasion and cryptocurrency charges.
He was also wanted for questioning over a murder and accused of rape - all of which he denied.
Following his death, his Instagram followers have questioned a mysterious 'Q' image that appeared shortly afterwards - an apparent reference to the conspiracy group QAnon.
Meanwhile, comments have also resurfaced in which the tech pioneer said he would never kill himself in prison - while his wife claimed earlier this week that authorities were "determined" to see him die behind bars.
'Q' post stirs conspiracy theorists
Minutes after McAfee's death was reported, a black, capital letter 'Q' was posted on his Instagram account.
The image appears to reference the warped conspiracy group QAnon, whose followers rocketed during the presidency of Donald Trump.
Q conspiracists subscribe to the discredited far-right theory that the former US president was waging a war against high-profile paedophiles running a worldwide child sex-trafficking ring.
It is unclear whether McAfee was a follower of the movement himself or who had control of his account at the time of his death. The post has since been taken down and his account has also been removed.
The post has prompted Q believers to question on social media the circumstances around his death, drawing links to the conspiracies surrounding Jeffrey Epstein.
The convicted paedophile was found dead in his prison cell in 2019 and McAfee posted a rambling message the same year refuting claims his death was a suicide.
Sharing an an altered photo of himself alongside Epstein, he wrote: "I never said Jeffrey Epstein was murdered. I said he didn't commit suicide. Not the same.
"Could be alive. Could have never existed. Maybe murdered. I dunno. I only know he didn't commit suicide."
Creepy predictions about death
McAfee and his wife also warned that he was being targeted by US authorities who were "determined" to see him die in prison.
Two years ago, he claimed that if he was ever discovered dead by suicide that he did not kill himself.
Showing off a tattoo that read "$whackd" on Twitter, McAfee said: "Getting subtle messages from U.S. officials saying, in effect: 'We're coming for you McAfee! We're going to kill yourself'
"I got a tattoo today just in case. If I suicide myself, I didn't. I was whackd. Check my right arm."
Tweeting from jail in October 2020, he added: "I am content in here. I have friends. The food is good. All is well. Know that if I hang myself, a la Epstein, it will be no fault of mine."
In a chilling Father's Day message days before his death, his wife Janice also claimed his "honesty got him in trouble with corrupt governments".
Janice, a 38-year-old former prostitute whom McAfee first picked up as an escort in 2012, said the media "continues to vilify him" and that he was a "father of many, loved by few".
She added: "John’s honesty has often gotten him in trouble with corrupt governments and corrupt government officials because of his outspoken nature and his refusal to be extorted, intimidated, or silenced.
"Now the US authorities are determined to have John die in prison to make an example of him for speaking out against corruption within their government agencies."
Notorious Spanish jail riddled with violence
McAfee was initially held in the Brians I prison complex near Barcelona after being apprehended while travelling through an airport in the Spanish city.
He was wanted by US authorities on tax evasion charges and was set to be extradited to America on the day he was found dead.
Later transferred to Brians 2, he appeared to prefer life behind bars in Spain compared to the US.
"Life in Spanish prisons is like the Hilton compared to the abject surrealism and dehumanization of American prisons," he wrote in a letter to Janice. "Here I am treated as a human being instead of a number."
Nonetheless, Bareclona's prison system has been rocked by a number of deaths recently, according to Mail Online.
The publication reports that in the last three weeks there have been four suicides in Catalan prisons, two of whom were inmates at Brians 2.
The prison also witnessed the brutal murder of an inmate by another lag shortly before McAfee was arrested.
The victim, who had been jailed for coercing minors and disabled individuals into performing sex work, was listening to an MP3 player when the prisoner stabbed him 29 times with a knife in his neck, chest and abdomen.
Gun nut on the run after murder riddle
After selling his stake in McAfee Antivirus to Intel for $7.6billion, the tech guru led a highly controversial life plagued by criminal allegations.
He regularly mocked his former company, once uploading a parody video entitled How to Uninstall McAfee Antivirus onto YouTube, in which he criticised the software while snorting white powder surrounded by scantily clad women.
Posting on his Instagram page, the tycoon would often share snaps of himself holding handguns and rifles, and was once detained for taking weapons and ammunition into the Dominican Republic.
In 2012, he fled from his home in Belize after police sought him for questioning over the death of his neighbour, Gregory Viant Faull.
The retired American builder was discovered by his housekeeper lying in a pool of blood inside his house.
A single Luger 9mm shell was found nearby, though there was no sign of a break in at the home.
A 2016 Showtime documentary "Gringo: The Dangerous Life of John McAfee" also aired allegations that McAfee had raped his former business partner and accusations he was involved in a second murder in Belize.
McAfee claimed that these incidents were fabricated, and alleged documentary-makers had paid their interviewees to talk in "third-world banana republic " Belize, according to Bloomberg.
In a statement obtained by Reuters news agency, the Catalan justice department said "everything points" to suicide following his death.
Security at Brians 2 prison tried to revive McAfee before his death was confirmed by the jail's medical team, a statement from the regional Catalan government said.
A court spokeswoman said a forensic team would need to perform toxicology tests on his body to determine the cause of death and that results could take “days or weeks.”
