I actually thought this was pretty good. It's a really good close-up shot. I don't think people appreciate the effort it takes to stack the pennies with such precision and balance like this :D Or - I guess people can't count :)
Nice macro. I do, however, think that I'd like to see it a little more high-key. The shadows on your whites do provide the image with a bit of depth, but I think them to be more of a distraction than an integral addition to the scene. Also, the gray border feels out of place. I do like borders, I just don't like the gray. 6.