I really like the Network Diagnostics tool of OS X when I have problems with my internet connections because of the red/green lights on the different parts of the connection. Unfortunately you can only open it from Safari and when there is no connection. It doesn't even show up in spotlight. So I looked it up and want to share it here. Source is macosxtips.co.uk When you have it open, right click on its dock icon and click "keep in dock". The tool itself is hidden away in system/library/coreservices so you can open it from there too. HTH!