It is now the ultimate status symbol in a town obsessed by status. Mr. Obama was spotted last week trying out his new BlackBerry  or actually a more sophisticated, encrypted variation  and aides say that he uses a computer in the study next to the Oval Office but that he has agreed to limit the number of people he would exchange e-mail with. In the process, he created a new measure for Washington to judge who really has the ear, or the thumb, of the president.

For decades, the capital scoured state dinner invitation lists and Camp David visitor logs for clues to who was in and who was out.

Former President Bill Clinton established a new class of insider with his Lincoln Bedroom sleepovers, although those usually came with an implicit price tag as he tried to raise campaign money. Former President George W. Bush provided fewer opportunities for the elite to demonstrate their eliteness by virtually abandoning state dinners, but there were invitations to his Texas ranch to clear brush, a dubious distinction, perhaps, during 100-degree Crawford summers.

Now there is President Obama’s e-mail, the first used by a commander in chief while in office. “This is the 21st-century version of the same special access that certain people are always granted to the president,” said Joel P. Johnson, a senior White House adviser under Mr. Clinton. “In F.D.R.’s White House, it was Harry Hopkins and Harold Ickes. There will be a similar select few in this White House.”

Those select few who have Mr. Obama’s e-mail address, say people informed about the matter, include Rahm Emanuel, the White House chief of staff; David Axelrod and Valerie Jarrett, both senior advisers; and Robert Gibbs, the press secretary. But cabinet members like the interior secretary, Ken Salazar, said they did not have it. Secretary of State Hillary Rodham Clinton is a frequent BlackBerry user, but a spokesman said he did not know whether she had the president’s address.