Web2.0Collage is a clever site that creates collages based on the icons of sites you've visited. But using it should remind you that your browser history is far from private.

University of Waterloo student Holden Karau decided to raise awareness of online privacy issues by creating a web-based application that turns a visitor's browser history into a miniature work of art.

And while the artistic merits of the collages that Web2.0Collage.com creates can certainly be debated, one thing is clear: our web surfing patterns are not private and can be easily accessed by any website that implements the same JavaScript code as Web2.0Collage.

The example image above was taken from my (non-cleared) browser history. While it doesn't reveal much of interest (WordPress, CNET, YouTube, LinkedIn, Digg and other common sites are represented) as it was taken from my primary work machine on which I tend to practice *very* careful surfing, my home computer might tell a different story!

Savvy web users already know that it's a good idea to regularly purge your browser's history and there are many browsers and browser add-ins that will automate or simplify this task for you. But many more people out there never do so, whether through ignorance or laziness. This lapse, Karau points out, is something to be wary of:

"Since browser history sniffing, which can be used to determine the websites a person has visited, is easily accomplished without the users knowledge or consent, the potential implications surrounding this loss of privacy are frightening."

If you're wondering what the possible risks are of having your browser history read by websites you visit, here's a partial list of potential hazards:

• Internet fraudsters can tailor their "phishing" (where they attempt to steal account and often financial information) based on which bank site you use
• Increasingly oppressive regimes can covertly observe the browser history of their citizens and us it to crack down on journalists, or citizens viewing independent media
• Job application sites could silently disqualify candidates based on their surfing habits
• Employers could use it to see which employees have been visiting job sites
• Insurers could raise premiums based on sites you visit
• Unscrupulous online merchants could dynamically shift prices on goods using demographic profiles constructed from browsing histories.

To clear your browser's history do the following:

in Internet Explorer
– Tools > Internet Option > Clear History

in Firefox
– Tools > Clear Recent History
(for better security, Tools > Options > Privacy Tab > check "clear history when Firefox closes"

in Google Chrome
– Wrench icon > Clear Browsing Data > select the options you want

in Apple Safari
– History > Choose 'Clear History' at the bottom of the pull down menu