He is a featured speaker at hacker conferences, an international expert on the hackerspace movement, and teaches introductory electronics workshops.

Altman was an early developer of virtual reality technologies, working at VPL Research with Jaron Lanier.

[4] Altman left VPL Research in protest when it accepted contracts with the United States Department of Defense.

[5] Altman co-founded Silicon Valley start-up 3ware in February 1997 with J. Peter Herz and Jim MacDonald (who is on the advisory board of Cornfield Electronics).

[10] In 2004 Altman released a one-button universal remote control called TV-B-Gone, to be used for turning off TVs in public places.