(FORTUNE Magazine) – From Interstate 5, two miles away, it looks like a puddle of metal, or maybe a crashed and melted space shuttle later attacked by graffitists. But after creeping through traffic in a nondescript Seattle neighborhood, you come upon what is in fact a giant shimmering jewel--the new Experience Music Project, designed with characteristic flamboyance by Frank Gehry and conceived, nurtured, and paid for by software billionaire Paul Allen and his sister, Jody Patton.

EMP calls itself a museum but takes its cues from a potpourri of precedents. Among them: the Fillmore auditoriums of the '60s, Nike stores, Disneyland, the wall of a teenager's bedroom, and your local historical society. It is surely the only nonprofit institution that includes a giant hall--with a 2,800-square-foot videoscreen--intended as a site for giant all-night parties.

What drove Microsoft co-founder Allen to shell out $240 million to build and furnish EMP was his profound love of rock music and his desire to help others both understand and participate in it. (Allen is a guitarist whose own band, Grown Men, recently released its first album.) EMP's mission is to celebrate "creativity and innovation in American popular music." To do that, it combines concert halls, exhibits--even a ride--with a plethora of hands-on activities. A sophisticated Website (emplive.com) allows visitors to continue the experience at home; a bus will take it on the road.

The whole thing has its genesis in Allen's near-obsessive love of Jimi Hendrix. In 1992, he started buying Hendrix memorabilia and laying plans for a Hendrix museum in Seattle. By 1994, Seattle had suddenly become the hottest city in rock, producing scores of successful grunge artists, notably Nirvana and Pearl Jam. So Allen broadened the project's scope to include all Northwest popular music. But putting that into context was impossible without examining all of American pop music.

As the scope grew, so did the need for space. Allen and Patton jettisoned the idea of installing their museum in a small warehouse and instead asked Gehry to produce something "swoopy."

The choice came long before the opening of the architect's world-renowned Guggenheim Museum in Bilbao, Spain. But it was eminently logical. Allen, Hendrix, and Gehry share a common trait: They all succeeded largely because of their willingness to push the limits of technology. Allen created Microsoft with his friend Bill Gates with the insight that the then-new microprocessor would make possible an entirely different kind of "personal" computing. Gehry has for years used software far more advanced than what most architects use--programs intended more for builders of airplanes. And Hendrix's path-breaking sounds were made possible by his willingness to experiment with technology, at least according to EMP chief curator Jim Fricke. "He combined a wah-wah pedal, a big amp, and distortion devices to turn it all into something completely new," says Fricke.

Now Allen's museum attempts to use technology to remake the "experience" of museum-going. EMP is the most wired museum in the world, relying in no small part on an ambitious device called the Museum Exhibit Guide (MEG), a powerful PC you carry on a shoulder strap. Just point it at an exhibit and listen through the headphones. Its 6-gigabyte hard drive is enough to store 12 hours of music in the MP3 format. It also contains a radio receiver, which, when operational, will pick up the 96 channels of broadcast audio. Spread around the building is enough cabling to circle the earth, along with one of the world's largest media servers, pumping out 15 megabits of data per second.

On a pre-opening visit, MEG appeared overly ambitious: It was too buggy to properly review. But if it works as promised, you could spend days and days here listening and soaking up vibes. At EMP's late-June opening, 2,500 MEGs were working, with 50,000 headphones on hand.

Allen hopes visitors will leave with more than just a sense of his extravagance. Says curator Fricke: "Paul said from day one he wanted people to come out energized to explore their own creativity, and to realize that the barriers between their heroes being onstage and themselves being there are much lower than they thought." In the Soundlab, you can pluck at a guitar or bass, or bang on a keyboard or drums, and there's a soundproof room where you and your chums can do all of the above at the same time. A guide works the mixing board while you play along with a recorded track. At your back are racks of amps--and you face huge video monitors that show a dancing, screaming, adoring audience. He Jimi, me Jimi, we Jimi.

EMP's weakness is its dependence on musical detritus. Many of the halls resemble a Hard Rock Cafe, although what's here aims to place music in historical context. The old guitars pale in comparison to video histories of various people, genres, and movements. A fascinating one documents, as an interviewee calls it, the "crypto-fascist acid glam" punk scene of Los Angeles around 1980.

If rock music and its history hold little interest for you, the building is still worth a visit. Gehry puts curves and contrasts in places you'd never imagine them; where Seattle's tourist monorail even passes through the building, the promontories and eddies resemble nothing so much as a windswept desert cavern. Of course, Gehry's creations are bound to seem less surprising as they begin to appear in more and more places--a concert hall being built in Los Angeles; a business school in Cleveland; an outdoor stage in Chicago; perhaps even another Guggenheim in New York.

The Seattle establishment has emitted a few whiffs of disappointment, even disdain, in response to EMP. But those naysayers had better be careful. After all, Allen is already accumulating an impressive art collection....

Experience Music Project 325 Fifth Avenue N., Seattle, 206-770-2700, emplive.com; admission, $20 (includes use of MEG)

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