In MIT parlance, a hack is an anonymous prank, a gentle spoof, usually of MIT’s administration. Yet some have taken MIT hacks seriously enough to write entire books about them. The most recent, Nightwork, includes an obituary of sorts, for a prominent association of hackers:

“THA–Technology Hackers Association, a now-defunct hacking group…”

Yet this, too, is a hack. I know, because I’m a THA member, and on a Friday night in May, my fellow members and I met in a Cambridge church rec room to celebrate the association’s 25th anniversary. On the surface, it looked like an ordinary gathering, not the legendary–and secretive–organization behind so many of MIT’s greatest hacks. A table display of locks gave it away: a veritable history of the hardware that has protected MIT’s laboratories, offices, and rooftops over the last 50 or so years.

“This is what MIT’s using now.” An earnest, red-haired young man plucked a lock barrel from the pile on the table and thrust it at me. The lock was distinguishable from the others only in that it was shiny. “It’s a Primus,” he said.

“Can you pick it?” I asked.

“Not yet. I can’t get past the double bitting,” he answered, referring to the second row of teeth on the interior of the shaft.

Having a table of locks to pick would be, to say the least, unusual at most reunions, but it’s emblematic of THA’s quarter-century reign as MIT’s premier hacking organization.

From its humble beginnings in a New House dorm room in 1980, the Technology Hackers Association has become the de facto caretaker of one of MIT’s greatest traditions. If the group didn’t exist, a few hundred hacks would never have taken place–though it does not officially claim credit for any of them.

Out of a membership of around 230 (of which about 10 percent are active at any given time), several dozen THAers from across the country had converged on Cambridge to celebrate an organization that, by necessity, operates outside the formal bounds of the MIT community. As often happens at such gatherings, the reunion broke down along generational lines. Old-timers wanted to reminisce and discuss their hacks openly. Current students were less forthcoming, and those who were willing to talk did not want to be identified.

According to founder Bryan Bentz ‘80, ‘82, the association grew out of “Freshman Shower Night,” when upperclassmen would throw freshmen into the shower the night before their first 8.01 physics exam. As a senior, Bentz organized the freshmen to oppose it. “I instinctively rebel against any form of hazing,” he explains. Bentz later took these freshmen (and a few upperclassmen) and formed THA “to get something lighthearted” into his life, he says. Membership would be for life, Bentz decided. Members received ID cards and numbers. He became number 100. ID numbers help preserve anonymity, and to this day, THA refers to members only by number in its communications.

The group pulled its first hack before Bentz left campus. According to John Pitrelli ‘83, SM ‘85, PhD ‘90 (THA member 101), the hack, which took place in February 1980, was “to fly a 16-by-11-foot Soviet flag saying ‘Stop the Draft’ from the fifth floor of the student center during a rally against draft registration.”

The first hack to gain public off-campus notice was a working phone booth placed on the Great Dome in 1982. This was followed in 1985, when the group parked a decrepit Fiat (owned by member 133) in Lobby 10 and refashioned the Infinite Corridor into the “Mass. Toolpike” (“tool” being an MIT term for studying really hard) with a $16,000 toll (the cost of tuition). The next year, the group addressed a campus housing shortage by creating room number “10-1000,” a dorm atop the Great Dome.

In between these elaborate, attention-getting hacks were innumerable smaller, less public pranks. For example, in the early 1980s the group kept a working phone line hidden on top of the Lobby 7 dome, from which students could call Mom and Dad. The association evolved into a haven for those dissatisfied with the more conventional student activities.

“After spending several stressful days of being a fish out of water at frat rush events [in the mid-1980s]…I went on an Orange Tour [an illicit nighttime tour of MIT’s rooftops and other verboten places] and saw another world,” says member 221, now an up-and-coming professor at a prestigious West Coast school. “For me, THA was essential for building confidence, getting experience, learning how to lead,” he says.

Today he manages a group of researchers and says the “accelerated project-management training” that hacking provided has “come in handy.”

The association’s best-known hack–the appearance of a campus police (CP) car on top of the Great Dome in 1994–required plenty of project-management skills. Although the Technology Hackers Association generally refuses to claim credit for its hacks, there was no shortage of car-hack participants at the reunion, and they willingly shared their stories.

Jeff Bigler ‘87, ‘88, number 205, revealed he was one of the masterminds behind the hack. “It all started when 248 bought a police light bar [the flashing roof lights on a police car] at a flea market,” he recalls. “We thought, ‘There’s got to be a hack here.’”

It took about two years for the stunt to develop. “Number 249 and some others went to a junkyard and paid a guy $100 to use anything off of an old Chevy Cavalier.” After that, Bigler says, it took about three months to pull the hack off . “We stored the car pieces in the basement of Senior House and would take them to 2-190 to work on a frame.” Did they worry about being discovered in a lecture hall? “No,” replies Bigler. “If anyone came in, they’d see a bunch of kids working on car parts. It wasn’t even all that unusual.”

But the hack itself certainly was, as was the amount of persistence and coordination required to pull it off . It took three attempts to get the car onto the Great Dome. One problem: a two-and-a-half-meter-high concrete barrier encircled the dome, preventing easy access from other areas on the roof.

“Then Dave Krikorian ‘91, number 180, developed wooden rollers to use. After that it went up pretty quickly,” Bigler says. The group knew the hack would draw media attention, but, says Bigler, they weren’t prepared for how much. By 8:00 a.m. the next morning, a large assemblage of photographers and reporters had gathered in Killian Court. Television news networks carried video of the hack, and photos appeared in newspapers around the world. The car itself became an MIT Museum exhibit.

Could the hack have happened without an organization like THA? Bigler thinks not. “Our group had done a number of hacks, and each hack raised the bar on detail, complexity,” he says. Number 221 agrees: “What [THA] does is promote the long-term memory of the hacking community so that lessons are cumulative rather than everyone starting from scratch.”

To many members, including number 221, secrecy is essential to the association’s existence. “Plausible deniability is important for the administration,” explains 221. “If the membership were known and the hacks were publicly credited, the Institute would know who to punish.”

This penchant for secrecy helps explain the group’s refusal to take credit for its hacks. “After all, an organization that no longer exists couldn’t possibly be pulling new hacks,” adds the group’s current leader, who is known as the chancellor.

And then there’s the matter of hurt feelings. “Nonmembers have been involved in hacks spawned by THA members,” the chancellor says. “To then claim such a hack as ‘a THA hack’ is wrong, given the contributions by those who are not members.”

The curious result is a group that disavows its greatest accomplishments. This shadowy mode of operation also leads to a mystique surrounding the organization, perhaps best summed up by Deborah Douglas, MIT Museum curator of science and technology, who calls the group “MIT’s version of Skull and Bones.” It’s an august comparison–a 173-year-old Ivy League club with ties to both presidential candidates in the 2004 election and a 25-year-old group whose idea of a good time is climbing around on rooftops. The chancellor dismissed the comparison, saying, “The only real similarity is an element of secrecy.”

Yet one wonders. Looking at the membership list, one sees physicians, an attorney, professors–including a distinguished member of the MIT engineering faculty–a national television personality, a high-level executive for a major European bank, and an entrepreneur who founded a $10 million software company. Maybe the comparison is not so far-fetched, after all. Members of this underground group credit it as playing a major role in their success. Let’s hope it remains “defunct” for another 25 years.