Q&A -- re. Pin Cube. As far as I know, pins at one time were sold in cubes.
I did a google search. I found a couple links with photographs (and prices) of real pin cubes. Look Here, here, and scroll down a bit here.
The Christmas Pin Cube pattern was from Just Cross Stitch - December 2004. The back, stitched area, says 100 pins w/motif. Picture of front in my previous post.
I see Ellen Chester has Pair of Pin Cubes on her web site. Next to the stitched models is the cardboard antique inspiration.
Edited to add: Per Staci, there is a pin cube pattern in the December issue of Sampler & Antique Needlework Quarterly magazine. Volume 45. (which I had forgotten about) It is designed by Kathleen Starr Watt.
If anyone has a source for other patterns, please advise & I'll add to this post : )