Since the earliest versions of CorelDRAW, I remember rotating shapes to create some cool patterns. It isn’t a particularly difficult task though there are several steps involved. It may also require a little bit of math to determine the best rotation angles.
GDG Optimum Rotate takes this kind of effect to a completely different level. It simplifies rotating objects to create patterns. But it can also do many more things that aren’t easily done without the macro. Make sure to look at the product page for a movie showing some of the possibilities as well as a detailed explanation of all of the options in the macro’s dialog box.