Install multiple instances of Internet Explorer!
Ah yes, the joy of running multiple instances of the worlds favorite browser at the same time. What could be more joyous than running IE 3, 4, 5, and 6?! I mean, who wouldn’t want to go old school with the Microsoft browser wonder?
For those that must have the classics, Tredosoft offers up a single installer which will bless you machine with IE3, IE4, IE5, IE5.5, and IE6. Why someone would feel inclined to do so is beyond me. But hey, when something as great as Internet Explorer comes around as a single installer, who would hesitate?

If you were developing diff internet programs and wanted to see what / if the product worked in all browsers, this would be really helpfull.