I like to use Eclipse\'s shortcut Ctrl + O which outlines the current source. Is there an equivalent shortcut in IntelliJ IDEA?
It opens a dial
All these answers are subjective, because they depend on your platform, keymap and IntelliJ version.
I believe the 'Structure' tool is what you're looking for. In Idea 13, View → Tool Windows → Structure will open the view, and along the way, the menu will show you the applicable keyboard shortcut for your setup.