Open Source Assistive Technology Software (OATS)
This is a great web site for locating open source (free) software that addresses a multitude of barriers to accessing the curriculum. http://www.oatsoft.org/
You can search the software database by the need that it meets, by the type or category of software, or see all the titles. (There are over 150 titles listed.)
You can also contribute toward projects developing new software or introduce software that you have developed. There is a forum area for discussion and a news section with the latest developments. There is something here for everyone.