The Greater New York Centennial Celebration -- dubbed "NYC 100" -- raises the curtain Oct. 26 on a unique series of play readings in association with the city's nonprofit theatres.

The 100th anniversary of the consolidation of New York's five boroughs into one massive unit (in 1898) has been recognized all year in the city, and now playgoers can be a part of it by experiencing (mostly free) readings of rare and popular works made famous in the Big Apple.

The festival begins 8 PM Oct. 26 with the a cappella musical, Avenue X, at Playwrights Horizons' Anne G. Wilder Theatre, 416 W. 42nd St. The staging is sold out, according to Natasha Caba of NYC 100.

The most aggressive reading so far is the Joseph Papp Public Theater's attempt to reassemble its original cast of 1993's Angels in America: Millennium Approaches on Nov. 16. The performance, which so far has original stars Ellen McLaughlin, Stephen Spinella, David Marshall Grant, Joe Mantello, Kathleen Chalfant and Geoffrey Wright attached to it, is sold out, according to Sarah Rayer of the Public. There is a waiting list, she said, so there's still hope.

"They're thrilled about doing it," Rayer said of the cast. "It was such a big part of their careers." Ron Leibman and Marcia Gay Harden have not yet been confirmed to recreate their roles in Angels. The reading is staged by Mantello. Among 14 works being read in full or in part over the nine-week series are Anne Nichols' Abie's Irish Rose (Jewish Repertory Theatre), Langdon Mitchell's The New York Idea (New York Theatre Workshop), George S. Kaufman's The Butter and Egg Man (Atlantic Theater Company), Clyde Fitch's Captain Jinks of the Horse Marines (Lincoln Center Theater), Casa Propia (Repertorio Espanol) and the aforementioned Angels.

Theatre buffs attending Captain Jinks Dec. 14 will get a rare introduction to the once-popular Fitch, mostly forgotten today because his work was so thin and of-the-moment. The comedy -- soldier woos opera singer -- was expected to run two weeks in 1901, but lasted seven months and introduced Ethel Barrymore to Broadway.

Organizers of NYC 100 asked theatres to be a part of the celebration by choosing a play that has been staged in New York City, preferably something relating to the subject of New York, or the city's history and heritage.

In the case of Abie's Irish Rose, considered a museum piece today, the historical value is great: It was one of the major smashes in American theatre history, running 2,327 performances.

Most of the readings are free, said Caba, underscoring the generosity of the nonprofits involved.

A highlight in the series is "NYC 100 Night of Historic Criticism," a reading of amusing, incendiary and thoughtful theatre reviews from the past 100 years in New York. The free reading, in association with The New York Times Company Foundation and the National Arts Journalism Program (NAJP) at Columbia University, is 8 PM Nov. 2 at the Clark Studio Theatre, Rose Building 7th Floor, Lincoln Center, 165 W. 65th St. Call (212) 831 2000.

The "NYC 100 Festival of Play Readings" includes:

8 PM Oct. 26
Avenue X by John Miler and Ray Leslee (1993)
Playwrights Horizons Anne G. Wilder Theater, 416 W. 42nd St.
(212) 279-4200 ($10; SOLD OUT)
8 PM Nov. 2
"NYC 100 Night of Historic Criticism"
Clark Studio Theatre, Rose Building 11th Floor, Lincoln Center, 165 W. 65th St.
(212) 579-4502 (Free)
7:30 PM Nov. 2
Abie's Irish Rose by Anne Nichols (1922)
Jewish Repertory Theater, Playhouse 91, 316 E. 91st St.
(212) 831-2000 (Free)
7 PM Nov. 16
Angels in America: Millennium Approaches by Tony Kushner (1993)
The Joseph Papp Public Theater, Anspacher Theater, 425 Lafayette St.
(212) 539-8521 (Free; SOLD OUT w/waiting list)
7 PM Nov. 16
Casa Propia by Dolores Prida
Repertorio Espanol at Gramercy Arts Theatre, 138 E. 27th St.
(212) 889-2850 (Free)
7 PM Nov. 16
You Can't Take It With You by George S. Kaufman & Moss Hart (1936)
The New Group
Theatre Row Theatre, 424 W. 42nd St.
(212) 647-0752 ($8)
8 PM Nov. 16
Winterset by Maxwell Anderson (1935)
The Lab, The Raw Space, 529 W. 42nd St.
(212) 252-2610 (Free)
8 PM Nov. 23
The Butter and Egg Man by George S. Kaufman (1936)
Atlantic Theater Company, 336 W. 20th St.
(212) 645-1242 (Free)
7 PM Nov. 30
The Indian Wants the Bronx by Israel Horovitz (1968)
Second Stage, 2162 Broadway
(212) 787-8302 Ext. 902 (Free)
7 PM Nov. 30
Luv by Murray Schisgal (1964)
Irish Repertory Theatre, 132 W. 22nd St.
(212) 727-2737 (Free)
7:30 PM Dec. 7
Stage Door by George S. Kaufman & Edna Ferber (1936)
Manhattan Theatre Club, Stage 1 at City Center, 131 W. 55th St.
(212) 399-3030 (Free)

8 PM Dec. 14
Captain Jinks of the Horse Marines by Clyde Fitch (1901)
Lincoln Center Theater, 150 W. 65th St.
(212) 362-7600 (Free)
7:30 PM Dec. 14
The New York Idea by Langdon Mitchell (1906)
New York Theatre Workshop, 79 E. 4th St.
(212) 460-5475 (Free)
8 PM Dec. 21
A Hatful of Rain by Michael Gazzo (1955)
Queens Theatre in the Park, Flushing Meadows Corona Park.
(718) 760-0064 (Free)
7:30 PM Dec. 28
Before Breakfast by Eugene O'Neill (1916)
Playwrights Theater of New York, Provincetown Playhouse, 133 MacDougal St.
(212) 714-7700 ($7)
-- By Kenneth Jones