Learn Microsoft Excel Online. Every day we post fresh Excel Tips, Tricks, Charts, Formula Examples, Tutorials, Downloads, Dashboards, Templates and Visualizations for your Inspiration, Success and Productivity.
I must say it is a really a quick and easy way to create hierarchycal data validation, especially when your data is not expected to change. And also you can see a useful featue how to create names! from selection.
This site is one of my personal favourite - not only because it is great to remember that this is the site from where I navigated to Daniel Ferry's Excel Hero blog. You can find a variety of useful (and mostly non-trivial) tips, add-ins, books here.