1. In this classic cold open from The Office , where Jim pops Dwight's exercise ball and he falls, the ball was actually expected to slowly deflate (and did so successfully in 13 takes prior!). But on one take, when John Krasinsky stabbed the ball with scissors, it immediately popped, leading to Rainn Wilson immediately falling to the floor.

It ended up being funnier that way, and they kept it in. You can even see Phyllis trying not to laugh right afterward and Krasinski running away. 2.

In another scene from The Office , Angela gets angry after Kelly kisses Dwight at a Christmas party and starts throwing ornaments at a brick wall outside. However, when Angela Kinsey , the actor playing Angela, was throwing the ornaments, they wouldn't break. She decided to go with it, hilariously giving up, screaming, and stomping on them.

3. On Friends , Ross said the wrong name at the altar because of David Schwimmer's real-life mistake. In a rehearsal for a different episode, David Schwimmer accidentally called Emily "Rachel," saying, "Rachel, the taxi's here" instead of "Emily, the taxi's here.

" Writer Greg Malins says this is the moment he came up with the Rachel/Emily name-switch idea. 4. A huge Parks and Recreation plotline also happened because of a brief unplanned moment.

In the Season 1 finale, after Andy attempted to describe his band's music to the group, Aubrey Plaza ad-libbed, "I totally get what you mean." Series creator Michael Schur said , "It was just a tiny, little throwaw.