Still surfing the Web with Internet Explorer 7? You'll probably want to update before shopping at Kogan, as the Australian electronics retailer has announced that it will penalize folks using Microsoft's obsolete browser. Customers who visit Kogan's site will see a warning page informing them that their software is outdated along with recommending that they install an alternative browser such as Chrome, Firefox, Safari or Opera.

If the user refuses to upgrade, they'll be forced to pay a 6.8% "Internet Explorer 7 tax" on their order. The 6.8% surcharge amounts to 0.1% for every month IE7 has been available, though it's unclear if the tax will increase each month or if it will remain at 6.8%. The company explains that it has kept its prices low by using technology to improve the efficiency of its business and Microsoft's six-year-old browser makes that tough.

"Our web team having to spend a lot of time making our new website look normal on IE7," Kogan wrote on its blog Wednesday. "It's not only costing us a huge amount, it's affecting any business with an online presence, and costing the Internet economy millions. Customers who enter our site using [IE7] can avoid the impost by simply downloading an up-to-date browser," including a more recent version of Internet Explorer.

"As Internet citizens, we all have a responsibility to make the Internet a better place. By taking these measures, we are doing our bit. This will help us increase our efficiency, help keep prices for all smart shoppers down, and hopefully help eradicate the world of the pain in the rear that is IE7," the company said. As of May 2012, IE7's global market share is estimated between 1.5% and 5%, depending on the researcher.

Update: Neowin tested the checkout process and the fee is reportedly removed at the last moment. Thanks for the heads up, madboyv1.