&gt; Can you cite a single widely used software that doesn&#x27;t have a FOSS alternative which works on Linux.<p>Woah, really? There are plenty.<p>Photoshop &amp; Lightroom debatable, but I can agree — nothing FOSS really <i>substitutes</i> them, unfortunately.<p>AutoCAD &amp; ArchiCAD. Solidworks. Pretty much all specific 3D modelling tools like Poser (though I don&#x27;t really need that last one).<p>Ableton, Cubase, everything from NativeInstruments, including sample libraries which sometimes are <i>the</i> reason why you need KONTAKT, and not some other sampler. U-he Zebra. Hundreds of various VST plugins from different developers: reverbs, phasers, limiters, etc. Often this stuff is quite trivial, but there just is some amount of domain knowledge which random opensource developer just doesn&#x27;t possess. That&#x27;s why free stuff available sucks or even doesn&#x27;t exist.<p>Decent speech recognition and text to speech. Nonexistent.<p>OCR is quite better, but still loses to commercial alternatives like ABBYY. Understandably so.<p>To put it shorter: pretty much any software which isn&#x27;t trivial to write or requires domain knowledge. The only decent examples of these in the FOSS world I can remember are Blender and Krita.