YouTube on any screen, any time. The YouTube APIs and Tools enable you to integrate YouTube's video content and functionality into your website, software application, or device.

http://code.google.com/apis/youtube/overview.html
http://groups.google.com/group/youtube-api?pli=1
http://www.programmableweb.com/api/youtube
http://www.ibm.com/developerworks/xml/library/x-youtubeapi/
http://www.ibm.com/developerworks/forums/thread.jspa?threadID=208711&tstart=30