NSFW unless crying in your office is acceptable.
Marina Abramovic's exhibit "The Artist Is Present" at MoMA made a lot of people cry. There's even a tumblr dedicated to how much everyone was crying.
Source: marinaabramovicmademecry
LINK: marinaabramovicmademecry
The premise of the exhibition was simple. Spectators were invited to sit across from her in complete silence while Abramovic stared at them. A lot of people were moved, but the tables were turned when a surprise guest showed up the opening night of the exhibition.