"Cool Jew" provides directions for making a shofar, the ram's horn trumpet used in synagogue. These begin with boiling the horn in water and baking soda for a couple of hours to remove cartilage and end with warnings about keeping the thing kosher: Don't drill holes in it. Don't paint it.
Finally, the most modern caveat: "Don't choose a shofar online. Before you buy, it's best to know how thy horn doth blow. Pucker up!"
Causes Lisa Alcalay Klug Supports
One Family Fund
San Francisco AIDS Walk