Earlier this spring I kept an eye on some tiny flowers that grew up in the cracks between bricks near my house. The flowers were at the end of fairly long stems, and when they opened were just a few millimeters in size. However, they were pretty uninteresting and did not look like a good macro subject, so I passed them by. A few days ago I took another look, and found that the now fading plants with tiny seed pods where each flower had been. The empty seed pods had an interesting shape... Here's a photo of one (click on the image for a larger view):

 This particular pod was 5mm in dimension, the image was taken at approximately 3x lifesized with a 50mm macro lens reverse mounted on extension. Thirty nine stacked images.