What is on your PC's drives?

In this example, I haven't used Javascript, or any other language at all. I've just used one of the native functions within your browser and pointed it at the appropriate drive when you click on one of the buttons. This page is in reality a form, and each button is the submit button.

When you click on a button it simply puts "file://'drive letter'|" in the Address field. This causes your browser to display the contents of the appropriate drive in the browser window. I don't see the contents, this is being displayed locally but it's a cute trick nonetheless which scares a few people the first time they see it...