How do I create a new folder using a keyboard shortcut?

Windows

Ctrl+Shift+N: Create a new folder in Windows Explorer.

Alternatively, use ALT+F+W+F on older Windows versions and MENU+W+F on the desktop.

Mac OS X

Create a New Folder shortcut using the System Preferences -> Keyboard & Mouse -> Keyboard Shortcuts panel. The system won't let you choose Cmd-N, but it will let you choose Cmd-Shift-N. Use that.

Desktop

The shortcut key should work there too.