Didn't know you could make Linux builds without being on Linux.
Viewing post in Please build your game for Linux (and Mac) as well!
Actually that's the whole point (one of them at least) of having a cross-platform environment. I can build for Windows and Mac on my Linux machine (and if Unity got their code straightened out I should be able to do WebGL builds a as well). And on Windows one can do Mac, Linux, and WebGL builds.
(Not to mention Android/iOS, and all the other platforms you may require a paid version for...)