Before the Osborne, Lee designed the Intel 8080 based “SOL”[1] computer from Processor Technology, the PennyWhistle[2][3]modem, and other early “S-100 bus” era designs. His shared-memory alphanumeric video display design, the Processor Technology VDM-1 video display module board, was widely copied and became the basis for the standard display architecture of personal computers. Many of his designs were leaders in reducing costs of computer technologies for the purpose of making them available to large markets. His work featured a concern for the social impact of technology and was influenced by the philosophy of Ivan Illich. Felsenstein was the engineer for the Community Memory project, one of the earliest attempts to place networked computer terminals in public places to facilitate social interactions among individuals, in the era before the Internet.
Lee Felsenstein was one of the original members of the Homebrew Computer Club, which formed in 1975 in response to the appearance of the Altair 8800 computer kit. With a handy yard stick, Lee “moderated” meetings at the SLAC Auditorium. He was less a chair than a keeper of chaos. In this heyday of the development of the first personal computers, Lee designed the Intel 8080 based “SOL”[1] computer from Processor Technology, the PennyWhistle[2]modem, and other early “S-100 bus” era designs. These existed in a market space with early generation hobbyist microcomputers from Altair, IMSAI, Morrow Designs, Cromemco, and other vendors. Felsenstein's shared-memory alphanumeric video display design, the Processor Technology VDM-1 video display module board, was widely copied and became the basis for the standard display architecture of personal computers.
In 1998, Lee Felsenstein founded the Free Speech Movement Archives as an online repository of historical information relating to that event, its antecedents and successors.