Hi, my own logic seems to have deserted me so i'm hoping someone can see how to deal with this issue. I'm building a small site which is primarily for showcasing projects. Each project must belong to a category and it can also belong to another project via a parent/child relationship. This is all fine.

The way i have set up the form for creating a project is simple, with a dropdown select box for the project category, and another (optional) dropdown select box where the user can pick a parent project to assign the new project to. However, I want to provide the option to have child projects unlimited levels deep, e.g a child project which is the child of another project which itself is also a child of a top level project. This is fine from the database design point of you, but I'm not sure how best to display this option to the user - all i can come up with is maybe adding a flag to child project options and using css to differentiate how they are displayed in the dropdown box, to show the nested effect...

If any of that makes any sense to anyone (not sure it does to me), i'd be grateful for any suggestions!