This picture is actually of soap.  I love it.  I'd like to try a similar frosting technique on my next cake.  Does anyone recognize what kind of tip was used to do this "frosting"?

Thanks guys!

It's hard to tell exactly what size the piping is, but it looks like a star tube (Wilton nos. 13-21, depending on size). If the star shapes are really big, try the 1M (the cupcake froster).