Okay, I woke up at 9.00 am PDT. Gmail was working fine. At exactly 9.21 am PDT, after seeing the temporary error (500) message, I got furious and tweeted. And, realized that I am not the only one through http://downforeveryoneorjustme.com/. By the way, this rant went somewhat viral with 1000+ clicks.
Very rarely, you see Gmail down? But, it just happened today. Next time, the easiest way to tell that a site is down only for you or the rest of internet users. Visit http://downforeveryoneorjustme.com or search via real time twitter. You can visit here for more update from Gmail.