Online retailer Kogan claims to have introduced the world's first Internet Explorer 7 tax for customers that purchase goods from the site using the browser.
The firm recently announced plans to impose a 6.8 per cent tax on any customers who use Microsoft's Internet Explorer 7 browser to buy goods through its Australian online site.
The company explained the move in a blog post, claiming it will help it keep product prices low.
"The way we've been able to keep our prices low is by using technology to make our business efficient and streamlined," said the post.
"One of the things stopping that is our web team having to spend a lot of time making our website look normal in Internet Explorer 7 (IE7)."
The company said 6.8 per cent surcharge equates to a 0.1 per cent price hike for each month the browser has been on the market.
"It's not only costing us a huge amount, it's affecting any business with an online presence and costing the internet economy millions," said the site.
"Customers can avoid the impost by simply downloading an up-to-date browser, such as Google Chrome, Mozilla Firefox, Safari, Opera or even a more recent version of Internet Explorer."
However, Andy Trish, managing director of the IT support provider NCI Technologies, said Kogan should simply tell customers that IE7 is not supported.
"Customers of Kogan have a choice, either upgrade IE and avoid the tax or shop around and find alternative websites that offer the same products at the same or cheaper price without the tax," he said.
"If it was me, on principle, I would shop elsewhere."
IE7 was launched in 2006. The newest version of the browser, Internet Explorer 10, is due to launch this autumn.
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