On-Line Videos 
 
 
This free downloadable screensaver (2 megabytes) for Windows features a selection of photographs from Images from the History of Public Health, a National Library of Medicine collection of photographs and illustrations.  You can visit the exhibit online as well.

To install the screensaver, decompress the file using a utility that supports the zip format and run the included setup.exe.  Then use your Windows Control Panel/Display/Screen Saver to select the PHS 200 screensaver.