Most people are aware of the process of DVD duplication, i.e. the copying of data from a disk to a DVDR (a recordable DVD). Usually we think of this in terms of copying movies or video, but there is also the scope for businesses to use this process for copying promotional material. Just think how much easier (and cheaper) it is to distribute DVDs rather than bulky catalogues and brochures. Of course, if you are serious about such promotional methods you should ensure that you use a reliable DVD duplication service, otherwise you run the risk of distributing poor quality discs which will only harm your promotional efforts.
To me, the benefits of such promotional methods are clear; less cost, less waste and lower distribution costs.