rsync -av --include='*/' --exclude='*' /src/path /destination/path
An example where we use it is when building Magento templates and themes, we copy the directory structure across but not the files so that when we need to, we can copy a file across from the base theme without having to create the directory structure before copying the file:
rsync -av --include='*/' --exclude='*' app/design/frontend/base/default/ app/design/frontend/default/default/