Joe Engressia, who legally changed his name to Joybubbles in 1991, played a pivotal role in the 1970s subculture of "phone phreaks" after discovering at a young age that he could make free phone calls by whistling tones, The New York Times reported Monday.

The precursors of today's computer hackers, the reign of phone phreaks ended when digitalization replaced the tone-based system.

Born blind, Joybubbles had an I.Q. of 172.

At one point during his childhood his obsession prompted his parents to go without telephone service for five years.

Joybubbles attended the University of South Florida but left after being caught making phone calls for friends at $1 a call.

He did menial work for most of his life before moving to Minnesota in 1982 and living on Social Security disability.

The cause of his death on Aug. 8 has not been determined.