Display a "[+] more" link when using a defined "Listing Depth"

This would be nice when you have a large list of terms and want to keep the page looking clean.
newegg does something similar
http://www.newegg.com/Store/SubCategory.aspx?SubCategory=32&name=Laptops...
some of the sections on the left display a link to view more options, which fade in when clicked.

Also, it would be better to allow a custom depth field instead of limiting it to 1-5.
thanks.