Excellent videos to help review or introduce material:
http://www.webelements.com/ Probably the best periodic table out there. Excellent for helping you visualize patterns and trends in the PT!
http://www.periodictable.com/ – Amazing amounts of information about each element, including high resolution photographs.
http://chemgametutor.com/ – A fun (but pretty difficult!) game that helps you review chemistry ideas.
ALL of my chemistry bookmarks: