Students could create faux Facebook pages for historical figures with comments and "likes" from relevant people during that time. They could also make faux profile pages, event pages, or groups to show their understanding of different people, events, or organizations in the past.
** Images are from http://coolmaterial.com/roundup/if-historical-events-had-facebook-statuses/. PLEASE NOTE THAT NOT ALL OF THE TEXT ON THE LINKED SITE IS SCHOOL-APPROPRIATE.**