At 80, Jonas Mekas is as busy as ever.

At 80 years old, Jonas Mekas could be forgiven for resting on his laurels. A legendary archivist and promoter of art film at his Anthology Film Archives, he is also a godfather of "diarist" and experimental film.

But retirement doesn't seem to be on his horizon. Mekas' summer show in Paris at the Musee d'Art Moderne is billed over Yoko Ono's simultaneous show, and in his native Lithuania, he's a prominent poet/playwright with a new book to be released in autumn. Indeed, Mekas is still busy extending the half-century of culture he's helped create. His great New York tableau Walden screens at Anthology on Sept. 11 as part of the Essential Cinema series, with Reminiscences of a Journey to Lithuania following on Sept. 12. The New York Film Festival also has a Mekas program slated for mid-October that includes Travel Songs, completed this year for the Paris show, as well as a piece from his Utopia Station Pavilion currently at the Venice Biennale.

Meanwhile, Mekas is working to raise $2.5 million to complete "this cathedral of cinema" at Anthology. Architect Raimund Abraham, renowned for midtown's 25-foot-wide Austrian Cultural Institute, has designed a research library to fit the 100-foot walkway at the rear of the landmark building-a walkway that's 12 feet wide. Conceived as shelves, it will make available vast paper archives, with a skylight strip illuminating down to a ground floor cafe.

With two theaters, more than 4000 films in storage, massive quantities of scripts and notebooks from avant-garde notables and Harry Smith's famous record collection, the institution is already a living monument to Mekas' passion for presentation and preservation.

Before beginning Anthology in 1970 at Joe Papp's Public Theater, Mekas started the Village Voice film column, founded the journal Film Culture and programmed activities at downtown's legendary Charles Theater, where he brought jazz great Sun Ra for his first New York show. As "underground" films were being ignored by Hollywood's commercial distributors, Mekas helped organize Film-Makers' Cooperative.

"We developed our own exhibition network," Mekas recalls in a voice still steely from that effort and gleeful at the results. "In 1961, if you counted universities and colleges where you could get a film screened, there were not more than 20. In 1971, American Film Institute's first guide listed 1200. Filmmakers had bombarded these institutions, and their work was shown." Their system came to be used by commercial distributors as well.

Anthology's Essential Cinema, consisting of some 300 titles ("the vision of the art of cinema as guided by the avant-garde sensibility") was established in 1968, requiring that Mekas devote considerable energy to film preservation. This devotion proved significant when production companies and universities began switching to video in the early 80s. Film labs abandoned huge film stores, and "we had no choice but to go to preservation."

At most, Anthology has indexed a third of its vast collections; artist Louise Bourgeois provided funds this August for an archivist. Mekas has worked without salary for years, his income coming from Europe, where the Paris show includes a 24-hour video commissioned by the museum and a remarkable "sound diary" installation done for French radio from tape snippets over the past 50 years.

In dream pages on display in Paris, Mekas comments on his own filmmaking: "I never film good performances or intense life. I only film bad performances and average life bits of which then I make intense life." In conversation, Mekas terms his film style "the diary form of cinema." When he began in the 50s, "diaristic experience was in literature... there was Norman Mailer. Mine is a notebook, almost a postcard kind of style, casual and very condensed, fragmentary.

"The other form that comes to mind is haiku poetry," he continues. "What's important is that you have to be completely here and now with the camera, very connected with the moment, the season of the year, the situation, while expressing into it the feelings and emotions."

Documentary maker Albert Maysles (Gimme Shelter; Grey Gardens) saw Mekas' massive 288-minute As I Was Moving Ahead (2000) "and [was] swept away." He distinguishes between directorial approaches that are "all technique or all feeling. Jonas is all feeling."

Jim Jarmusch, invited by Mekas to shoot his first Coffee and Cigarettes short with Roberto Benigni in Anthology while it was still being renovated, adds that, "What's amazing esthetically about Jonas' work is that he perfected the film diary form. It's different from cinema verite; it's not just documenting, it's very personal at the same time, like poetry verite. It's something very much his own."

"Jonas is one of the only genuine revolutionaries left, and I really admire that," says director Peter Bogdanovich, who met Mekas at the end of the 50s while first doing theater. "He was very encouraging to me, and very encouraging to people just starting out. We'd attend screenings; we'd go to Hollywood pictures, too, then talk about how crappy they were. Or about how great one or two were."

In these blog-heavy days, opportunities to view Mekas' film haikus offer renewed appreciation of what this master activist has recorded and illuminated for posterity.