http://www.mathsoft.com/browser/index.html
All development ceased.

Mathbrowser is an old 32-bit Windows application based on Mathcad version 5.0. It was made
freely available in 1995 so that users could learn about Mathcad as a computing environment and as a
vehicle for publishing mathematics on the Web. 

Much of the browser functionality and other features are now part of the current Mathcad 7, and can
be experienced by downloading the FREE read-only version called Mathcad Explorer. The current
Mathcad Explorer is much preferable since it incorporates Microsoft® Internet Explorer for web
browsing, allows you to open either Mathcad worksheets or Mathcad electronic books off a local file
system or over the Web, and provides access to most of the mathematical features of Mathcad 7
Professional.