Be wary of posting pictures of that wild party on Facebook and other social networking sites, because they might come back as ghost of the past to haunt you when you try to get credit, homes or jobs as adults.
Lenders, employers and landlords are increasingly using complex data mining tools to capture all the publicly posted data we supply to Facebook, Twitter, Flickr and any other social media network or blog to build data-rich profiles of our privates lives, revealed internet privacy experts.
While most of the focus has been on the marketing potential of data captured by Internet data companies such as Experian and Rapleaf, not many users of social networking sites have yet considered the impact of companies using it to build a snapshot of their lives for assessing credit or insurance applications or employment prospects.
However, this is exactly what some organisations are doing, said Geordie Guy, vice-chairman of Electronic Frontiers Australia. "The big growth area [for data mining technology] is credit," the Sydney Morning Herald quoted him as saying.
Cyber psychologist Dr Michael Carr-Gregg said teenagers were oblivious to the relentlessly public nature of the internet and do not think twice about acting out their passions and making their mistakes online.
In addition, they also use social networking as their primary form of socialisation and communication, he said.
They are also much less discriminating when it comes to accepting "friends" online that they might not know, and unaware how easily they can be traced from photographs with identifying features such as school uniforms.
The real scandal is the lack of adult supervision and monitoring online, said Carr-Greg.
"Reclaiming your online identity is like trying to unbake a cake. If potential employers have seen you drunk with your top off, you can't undo it," said Roger Clarke, chairman of the Australian Privacy Foundation.
Guy said that even the most clean-living Internet profile can be let down by the behaviour of housemates, family or other regular associates.
"Several companies mine data to the extent that, if they trawl social networks and see you or your close associates partying too much, it might affect your credit eligibility," he added.
While internet researchers don't provide banking or credit records alongside online profiles, many of their customers already have access to this data, and there is no legal barrier to them referring to an online dossier to assess your creditworthiness.
Guy said insurance companies could also stand to gain a great deal from pattern matching your personal data on a historical basis with that of your associates.