"Several of Burden's other performance pieces were considered somewhat controversial at the time: another "danger piece" was Doomed, in which Burden lay motionless in a museum gallery under a slanted sheet of glass, with a clock running nearby. Unbeknownst to the museum owners, Chris was prepared to remain in that position until someone interfered in some way with the piece. Forty-five hours later, a museum guard placed a pitcher of water in reaching distance to Burden. Burden then smashed the glass, and took a hammer to the clock, thus ending the piece."
http://en.wikipedia.org/wiki/Bob_Flanagan
Two different side of the same kind of currency. I always like thinking about this sort of expression, because while it might not be defined by all as "art" , it definitely hold rare forms of expression.
I think I always sympathized most with Flanagan because he could have and should have died at any moment basically, so his work very much seems born from an introspective place , where as Chris Burden's seems to be a bit more an exercise in taking things to the limits, more for the people than himself perhaps.
Tossing up this blog just to see what's what in people's minds about this stuff.