Gmail was down on September 1st, 2009, for everyone.  How can we tell?  Google's Apps Status Dashboard:

Video:

Learn about the Google App Engine system status dashboard.

Screenshot:

Google Apps Status Dashboard offers "performance information" on Google Apps services.
URL: google.com/appsstatus

The screenshot above, taken on September 1st, 2009, shows that Google Mail's service was "disrupted" on that day and started on August 31st, 2009, the day before.  Use this for future reference when you cannot log into Gmail.

Also See:

• Webmaster Articles
• Articles - Full Listing

External Links:

• Gmail
• Google Apps Status Dashboard

About the Author:  I am Matthew Doucette of Xona Games, an award-winning team-of-two indie game development studio working on Xbox 360 and PC games.  We have released Decimation X, a 1-4 player shmup, which is Japan's #1 best selling #1 top rated Xbox LIVE Indie Game.  We are currently working on Duality ZF, a groundbreaking 1-4 player shmup.  It features dual play, the ability to control two fighters at once, a beautiful electronic Imphenzia soundtrack, and a massively upgradable 32-stage spread/laser weapon system.  4 player dual play allows up to eight fighters at once.  Many of these features are never before seen shoot'em up firsts.  Check out our Duality ZF trailer and help spread the word with our official dualityzf.com website.  Coming soon to Xbox LIVE Indie Games.

*Also known as a shmup or 2D shooter.