Just the implementation and mine does not require Calibre (I know the plugin can be used without Calibre, but it is not its primary use case).
No acsm. It's books protected by Adobe DRM.
I have just created an alternative to knock (and other tools, just going for the simplicity of knock) for downloading ACSM files. Thought some of you might find it useful. It is still pretty early in its development, but it is working.
Just the implementation and mine does not require Calibre (I know the plugin can be used without Calibre, but it is not its primary use case).