Sondheim's books include the anthology Being on Line: Net Subjectivity (1997),[1] Disorders of the Real (1988),[2] .echo (2001),[3] Vel (Blazevox, 2004-5), Sophia (Writers Forum, 2004), The Wayward (2004),[4] and "Writing Under" (2012),[5] as well as other chapbooks, ebooks, and articles.
He explores notions of the 'abject' in the masculine and feminine online, and more recently has dealt with the machinic using the language of computer code to articulate novel forms of identity in cyberspace.
His work crosses over between philosophical explorations and sound poetry and more recently he has returned to the language of music using the tonalities of a wide range of ethnic instruments.
In 2009, Sondheim was working on a book examining the phenomenology and foundations of the analog and digital, and another on developing an aesthetics of virtual realities and avatars.
Broken Theory's preface is written by Maria Damon, and the volume contains a lengthy interview with Sondheim conducted by the art historian Ryan Whyte.
The significance of The Internet Text is as a document or residue of Sondheim's diverse writings and performances, and also as a philosophical reflection on computer mediated communication and online culture.