Agreed with Benvolio...These are definitely not C4D's. The name C4D stands for the main program used to create them- Cinema 4D. Now there are other programs that do the job but the name has stuck with the biggest program like people saying "Photoshopping".
Dragonkiller in that signature you posted you are correct C4D's are all in the background. But the images provided in this shop aren't meant to be used this way. Fractals are there more to add flow to the piece.