If you are an avid user of gmail you might have noticed an extended outage the morning of 24 Feb. In response to the outage Google created an apps status board that shows you information on current and past issues with any of the Google applications. You can view the status board here.
One great tool I recommend if you do use Gmail is the offline application. This allows you to view and create emails even when you aren't connected to the internet. Then when you do connect Gmail automatically downloads any new messages and sends any messages sitting in your outbox. Learn more about this feature here.