YouTube and various other tools now make it easy to share videos with your users. But what about your users with hearing impairments? Include captioning on your videos so that deaf users (or even people using computers without speakers) can watch the video and still understand the message. We've even put together a list of tools to help create captioning on your videos.
Web Captioning Overview - WebAIM
This article is a general discussion of captioning video files. It takes a top-down approach, explaining basic concepts rather than getting into detailed techniques for each media type.
Self-paced online tutorial designed to show you how to make multimedia accessible for individuals with disabilities... transcripts, captioning and audio descriptions.
Flash Accessibility - WebAIM
Basic overview and how-tos of Flash accessibility.