I have seen dark green and dark red backgrounds for Christmas table runners, black backgrounds for jewels and brights, medium dark blue background for blue-and-white floral windows.
BUT - you must-must-must check out this 2008 book by Lynne Edwards "CATHEDRAL WINDOWS: The Classic Folded Technique and a Wealth of Variations." The cover of the book only begins to open the door of creativity. Here's the amazon.com weblink:
http://www.amazon.com/Cathedral-Wind...7610286&sr=8-1
Use the LOOK INSIDE function to check out some amazing photos. This book knocked my socks off.