Ask Slashdot: Which Apps Aren't Available on Linux?

Have you ever needed a Linux application which only exists in the Windows world? Long-time Slashdot reader BrendaEM writes:Windows does have a lot of useful app (but smaller than "power apps"). Some of these are closed source, some are open, but they're not all available in Linux yet.
My list would have to contain Gimp Tookit versions of: IrfanView image manager, which I think is unequaled in Linux (though it does work to some extent under Wine). I also miss the full version of 7-Zip, because of