The Thundercat Consulting site uses a device called access keys. This allows a user who may have difficulty in using pointing devices such as a mouse, to get around the site using the keyboard.

How To Use Access Keys

Microsoft Windows Systems

• Microsoft Internet Explorer 5 or later - Press the "Alt" key and the relevant letter, then press the "Enter" key.
• Google Chrome - Press the "Alt" key and the relevant letter.
• Firefox - Press the "Alt" key and the relevant letter at the same time.
• Opera - Press "Shift+Esc" keys and the relevant letter.

Apple MacOS X Systems

• Safari 4 or later - Press the "Ctrl" and "Option" ("alt") keys with the relevant letter at the same time.
• Google Chrome - Press the "Ctrl" and "ALT" keys with the relevant letter/number at the same time.
• Other Browsers - Press "Ctrl" and "Shift" keys and the relevant letter at the same time

Please see http://en.wikipedia.org/wiki/Access_key for further details.