Useful Timelines of History of Art
Heibrunn timeline of Art history 
Smarthistory by Khan Academy - great resources!
A long clear visual chart of key movements in art
A well-indexed timeline (http://www.essentialvermeer.com/) 
Art history timeline of great paintings in the modern era (http://www.non-solo-arte.com/)Timeline of major art movements across the centuries
Major modern art movements of the 19-20th century
Timeline of major art works in the AP Art History exam
Other useful timelines:
http://chaos1.hypermart.net/fullsize/artrenfs.gif
