http://youtube.ddicad.com/home A quick tip on how to use blocks within layout sketches in order to take advantage of tools like path, belt/chain and traction relationships in designing mechanisms.
http://youtube.ddicad.com/home This quick tip shows the feature set in the free eDrawings viewer as well as how to markup files and send the info back to the publisher.
http://youtube.ddicad.com/home This video displays some options for using selection tools at the part and assembly level of SolidWorks. Some of the tools have been there, while some were added just recently in 2009 SP2.