MobileMe from Apple, the replacement for .Mac, is failing right now. You can’t use the web apps. But you can use SMTP and IMAP from Mail. iDisk doesn’t work, Galleries work, Web Pages supposedly don’t work.
UPDATE: Web Pages DO work. Here is a sample I just published.
UPDATE 2: You can access the webapps but right now they fail.
UPDATE 3: The webapps are a bit better now, but still have issues.