<p>It's a good thing we don't yet have Smell-o-Vision: A sulfur compound has the starring role in this winning picture from the 2010 Small World Microphotography Competition, whose top images were announced Wednesday.</p><p>To make the image, John Hart of the University of Colorado, Boulder, melted together sulfur (<a id="o3j:" title="picture" href="http://science.nationalgeographic.com/wallpaper/science/photos/minerals/sulfur-source/">picture</a>) and acetanilide, a toxic substance once used as an antiseptic. The mixture then formed crystals, seen here magnified ten times under specially polarized light.<br><br>Sponsored by Nikon, the annual contest showcases "the beauty and complexity of life as seen through the light microscope."</p>