Most people find these repulsive, but I find them fascinating. They appear out of nowhere but always announce their presence far and wide by the strong smell (usually described as disgusting but I think of as VERY organic). They grow on decaying wood and are fairly common along the gulf coast states. Their peak season is October through March.
The slimy brown portion is the smelly part and the part which also contains the spores. Flies are attracted to the smell and spread the spores to wherever they travel next.
Different species come in a variety of colors and formations but all have the distinctive smell. The photo here is of Clathrus columnatus.
If you'd like to know more there is excellent information at Mushroom Expert and at floridata.com