Base jumpers parachute from the Rialto. Credit:Colby Swandale Last year, four men in business suits ordered a drink at the bar at the top of the Rialto in Melbourne, then wedged the balcony door shut, donned the parachutes they had hidden in suitcases and jumped from the building, James Bond-style. Few people wanted to see the men - who were never caught despite saturation media coverage - prosecuted for the stunt. These are one-off examples of high-risk escapades, but the internet has brought about a new era of pseudonymity; one in which outlaw figures can engage with followers, media and law enforcement for years while their true identities remain unknown. What they have in common is they are (or were) wanted by the authorities, and often establish a cult following. They all claim libertarian, anti-capitalist, anti-authoritarian philosophies and have accumulated substantial wealth while maintaining anonymity. British graffiti artist, social commentator and political activist Banksy is perhaps the best known of these. He has been active as a street artist since 1992 and over the years has moved up to pranks such as installing his own works in famous galleries and museums, or installing a life-sized mannequin dressed as a Guantanamo Bay prisoner as part of a Disneyland ride.

Although technically a vandal, it's unlikely law enforcers are searching for Banksy, whose works can command upwards of $1 million at auction. And chances are, if Wikipedia is to be believed, we probably know who he is but have decided to turn a blind eye in favour of the myth of the anonymous bad boy with a message. Two figures who most certainly feature on law enforcement's radar are Satoshi Nakamoto, the inventor of crypto-currency Bitcoin, and Dread Pirate Roberts, owner of online illicit drugs emporium Silk Road. Silk Road operates openly, in defiance of authorities, as an international marketplace bringing together buyers and sellers of everything from steroids to ecstasy, cocaine and heroin. It uses Bitcoin exclusively for transactions. Bitcoin is a borderless digital currency that started out as a valueless computer code, but now has a market value of more than $US1 billion ($1.1billion), of which Silk Road's annual turnover probably accounts for between $20 million and $30 million. Not surprisingly, the website doesn't make its figures available. Bitcoin was unleashed in February 2009, when a modest post appeared on an internet forum by someone calling himself Satoshi Nakamoto (male, 38, Japan): ''I've developed a new open source P2P e-cash system called Bitcoin … Give it a try.''

In the months after, Nakamoto made a series of posts on his forum, bitcointalk, describing the project in detail and revealing the motivation behind his invention as the mistrust of banks after the global financial crisis. As experts recognised the genius in his invention, interest moved from a few early adopters in the IT sphere to the finance pages of the mainstream newspapers. And then, in early 2011, Nakamoto quietly disappeared. Intrigue soon began to build about Nakamoto's true identity. It became apparent that no such person as Satoshi Nakamoto ever existed, nor did his website lead anywhere but dead ends. Nakamoto had stage-managed a believable persona well before launching the Bitcoin Project. The 364 posts he made on bitcointalk, while lengthy and technical, revealed little about their author, other than he, she or they were a genius who had thought of and plugged every possible problem with, and potential attack upon, the currency. In October 2011, The New Yorker printed a well-researched piece that identified Nakamoto as Michael Clear, a student of Trinity College, Dublin. Shortly after, Fast Company countered with equally compelling - and equally circumstantial - evidence that Nakamoto was a pseudonym for not one but three Munich-based men who had worked together to create Bitcoin.

The accused all emphatically denied it. But as Clear told The New Yorker, ''Even if I was I wouldn't tell you.'' Another accused, Neal King, told Fast Company: ''I'm cashing in on Warhol's prediction of 15 minutes of fame - albeit for something I didn't do.'' There has since been a flurry of investigation and speculation by journalists and internet sleuths. Some surmise it is those who have much to gain from the currency's success; perhaps the head of the Bitcoin Foundation or cryptocurrency exchange, Mt Gox. Others believe it is a pseudonym for a disruptive government or the CIA. American IT sociologist and philosopher Ted Nelson named maths genius Shinichi Mochizuki (male, 44, Japan) in April this year but, again, evidence was weak and he denied it. As attempts to locate Nakamoto fail, his cult status grows. He doesn't appear to have made a single mistake yet; not in the code behind his invention, nor in covering his tracks, despite there being few people in the world who could possibly be him. Although unclear whether he has committed any crime, an FBI report leaked on the internet last year expressed concern at the application of Bitcoin for illicit purposes, thanks to the anonymity careful users can maintain in transactions. Nakamoto could be accused of conspiracy to engage in money laundering or some form of tax evasion or a law against disrupting markets. One of the illicit businesses named in the FBI report was Silk Road, led by the enigmatic Dread Pirate Roberts. Roberts is an active and visible member of Silk Road's large community, where he is hailed as a hero by those who believe it is their right to buy drugs without the interference of law enforcement bodies.

When asked why he was able to remain anonymous despite manhunts by authorities and journalists, Roberts said, ''Because my life, liberty and mission are more important to me than fame, convenience or comfort.'' He is the one person in this article to whom not a single name of a real person has been linked. Indeed, the only names that have been raised in speculation of Roberts' identity are other pseudonyms. One is BeHe, a bitcointalk.org user who ran a suspected ponzi scheme through the forum during 2012. Many thought it was a money laundering scheme that accepted investors' Bitcoins and returned them to Silk Road's funds. The other is Nakamoto: according to The New Yorker, he briefly surfaced in April 2011, when he said he had ''moved on to other things''. Silk Road was born and announced on bitcointalk in February 2011 and was instrumental in the rise in the currency's value in 2011, although it no longer depends on the site for its stability. But the evidence of either of these being true is flimsier than the circumstantial evidence linking Nakamoto to various people. Although both are prone to writing lengthy missives in their respective forums, Nakamoto's were all technical and scientific in nature, while Roberts espouses his agorist philosophy, sets reading challenges in his ''book club'' for member discussion and has even hosted a movie night, with site members around the world simultaneously watching and discussing V for Vendetta. Nakamoto uses UK English; Roberts' writing is in US English. Although many would be appalled at the notion of drug dealer as hero, those who are against prohibition believe Silk Road offers a better, safer way for users to buy the drugs they will acquire anyway. As one member puts it, ''I came for the drugs and stayed for the revolution''. Forbes recently published a collection of Roberts' quotes, describing him as a ''principled libertarian and cypherpunk in the same vein as WikiLeaks founder Julian Assange and Bitcoin creator Satoshi Nakamoto''.

In true cult style, his devotees keep begging to give him more money, despite the huge sums he earns in commission. They offer their services in IT or to work as moderators of the forums for free. When the site is unavailable due to malicious attacks or infrastructure failure, members offer to take up a collection to help instead of demanding it be fixed with the profits they provided. Roberts never accepts such offers, though the moderators of the forum were unpaid until early this year and some people donate money ''to the cause'' anyway. With a curt admonishment, Roberts denied he is the object of cult-like devotion : ''don't go getting sensationalist on me now''. Another theory is that the person now posting as Roberts may not be the founder of the site - the clue is in the name. When the marketplace started, the owner simply went by the name Silk Road. But in February 2012 he wrote: ''Silk Road has matured and I need an identity separate from the site and the enterprise of which I am now only a part. I need a name. Actually, I already have a name picked out … It is perfect on so many levels.'' He revealed this to be Dread Pirate Roberts - a character from The Princess Bride who is not one man, but a series of individuals who periodically pass the name and reputation to a chosen successor without anyone else knowing. The original owner of Silk Road may well have sold the business along with the goodwill of his name, and is now sipping cocktails in the Bahamas. But as with many outlaws, it may be the money trail that leads to their undoing. Some of D.B. Cooper's loot was found in river lands in 1980, leading to the theory that he never survived the jump. Banksy's many commercial interests mean he must have accountants and advisers who know him. Bitcoin has the unique feature of providing anonymity for holders, while every transaction is public. In May 2012, sleuths of bitcointalk identified Silk Road's Bitcoin ''wallet'' containing the equivalent of $55million at today's rate. The coins were subsequently moved, presumably laundered somehow, and have yet to be retraced.

Last month, blogger Sergio Lerner uncovered a hoard of about $120million in Bitcoins that are owned by a single entity, and that entity began mining right from block one. Evidence points to the stash being owned by Nakamoto. That the coins remain untouched has sparked another round of conspiracy theories, such that he is dead, that the coins are held on a corrupted hard drive, or that he can't cash out without destabilising the currency or revealing his identity. ''One constant of outlaw heroes is that they are always villains to one or more sectors of society, particularly those holding power,'' Seal says. There is little doubt that Banksy, Nakamoto and Roberts fit that bill. @EileenOrmsby is a Melbourne writer who blogs at allthingsvice.com