Color Oracle is a colorblindness simulator for Window, Mac and Linux. It takes the guesswork out of designing for color blindness by showing you in real time what people with common color vision impairments will see.

Color Oracle applies a full screen color filter to art you are designing – independently of the software in use. Eight percent of all males are affected by color vision impairment – make sure that your graphical work is readable by the widest possible audience.

The following is NOT the Web Content Accessibility Guidelines (WCAG) 2.0. It is, however, a simple checklist that presents our recommendations for implementing HTML-related principles and techniques for those seeking WCAG 2.0 conformance. The language used here is significantly different from the official WCAG 2.0 specification (http://www.w3.org/TR/WCAG20/) to make it more easily implemented and verified for web pages.

NonVisual Desktop Access (NVDA) is a free and open source screen reader for the Microsoft Windows operating system. Providing feedback via synthetic speech and Braille, it enables blind or vision impaired people to access computers running Windows for no more cost than a sighted person. Major features include support for over 20 languages and the ability to run entirely from a USB drive with no installation.

thoughts on heading elements, see Roger Johansson comment

aDesigner is a disability simulator that helps designers ensure that their content and applications are accessible and usable by the visually impaired.

Voice browsers and screen readers read aloud the text on Web pages and are used by visually impaired people. However, these devices are less effective with certain kinds of content, such as highly graphical material. Web developers can use aDesigner to test the accessibility and usability of Web pages for low-vision and blind people.

aDesigner also helps users to check accessibility of ODF documents and Flash content. It also has accessibility information (MSAA/IA2) inspection functions.

WAVE is a free web accessibility evaluation tool provided by WebAIM. It is used to aid humans in the web accessibility evaluation process. Rather than providing a complex technical report, WAVE shows the original web page with embedded icons and indicators that reveal the accessibility information within your page.