I use this YouTube video to introduce the review of 8th grade curriculum. It gets the students' attention and activates prior knowledge. (I tried to embed the video, but could not access the code. Therefore, I linked the video.)
Discovery Education also has excellent clips to enhance student understanding of historic topics. http://player.discoveryeducation.com/index.cfm?guidAssetId=482EEFEF-1941-41C2-8F42-203A1281043D&blnFromSearch=1&productcode=US
Both of these sites are good to show students primary sources. All of the clips need to be cited and this models appropriate use to students. It is important to help them navigate and use the internet responsibly.
Dropboxes are useful so that assignments/lessons/videos can be open to anyone who has the link. Materials can be edited by others and it eliminates the need for external storage. Dropbox is accessible anywhere.