Since we all know not everyone reads the Feedback Forum, I am quoting Illia's post here, so the information can be seen when you go come to the home page:

Hi, We're having issues with a denial of service attack this morning, which is... denying service. Apologies for the sporatic downtime, but as we track down the source of the attack, it may be necessary to drop the main system offline periodically.

Thanks for your patience and understanding!!!