When the Class of 2000 officially celebrates the beginning of its 100-day countdown until graduation at the Hong Kong restaurant tonight, the location of the party will be especially significant: it was the favorite hangout of Conan C. O'Brien '85, who class officials confirmed will be this year's Class Day speaker.

O'Brien, who is the host of NBC's "Late Night With Conan O'Brien," will return to his alma mater to speak at the June 7 event--15 years after he himself graduated from Harvard.

His selection as speaker comes after more than three months of discussions by the Class Day speaker committee, composed of class marshals and House representatives.

In comparison to other Class Day predecessors over the past five years--former U.S. Senator Alan K. Simpson (R-Wy.), former Mass. Gov. William F. Weld '66, Quincy Jones, Tom Brokaw and Hank Aaron--O'Brien is a significantly younger and less traditional choice.

But some students involved in the selection process said his youthfulness is what made his candidacy for speaker so intriguing.

"There's no reason that the speaker has to be a gray haired man," said Justin M. Krebs '00, first class marshal and co-chair of the selection committee. "Not too long ago [O'Brien] was an undergrad who didn't know what he was going to do with himself--he went off with the same mixture of hope and apprehension that most of us probably have."

In addition, students said they expect O'Brien's work as a comedian will allow him to offer Harvard undergraduates a different kind of inspirational message than older, generally more serious speakers.

At O'Brien's own class day ceremony in 1985, for example, then- New York Governor Mario M. Cuomo touched on tax reform issues in his address to the senior class.