Kogan, an online retailer, has introduced an Internet Explorer 7 tax on its products. Citing the increased amount of time that Web developers must devote to building their sites in order to support a long-outdated browser, users purchasing items from Kogan with IE7 will pay a 6.8 percent tax on their total. Frustrating for IE7 users? Yes. The first method that may actually get those users to switch to a modern browser? Maybe.