AnyBurn

In what is it the best free software available in the world?

A lot of ligtweight burning softwares propose the same functionalities, even better.

Freeware, not open source.

A permission is required in the case of re-packaging such softwares.

Not a donationware.

Such software products are generally proposed as donationwares, or have a paid version including advanced features. This proprietary software gives nice features + free support, for free. Which is extremely suspicious IMO.

AnyBurn has a feature that none of currently available burning apps in PortableApps has - Copying disk to image file as BIN/CUE format. Neither cdrtfe nor InfraRecorder has this feature (saving as ISO format only).
The developer of the app has provided a portable version of it but it still leaves some unwanted leftovers at "%USERPROFILE%\AppData\Roaming\\anyburn\".