The Academy Awards celebrate actors for their work on film, but sometimes their most emotional performances take place on the Oscar stage.

After all, Hollywood's biggest night is often where the dreams of many stars become a reality, and with that, a lot of tears. Here are some of the most sob-filled Oscar moments in recent memory.

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1. Nicole Kidman: Best Actress, The Hours (2003)

Despite a valiant fight to hold back the tears, Kidman couldn't stop the waterworks from flowing.

"Russell Crowe said, 'Don't cry if you get up there,' and now I'm crying," she said.

2. Natalie Portman: Best Actress, Black Swan (2011)

Portman couldn't have been more grateful to take home the award, but she admitted that an even better prize would have been to work with her fellow nominees Nicole Kidman, Jennifer Lawrence, Annette Bening and Michelle Williams.

"I'm so in awe of you," she said.

3. Ben Affleck: Best Picture, Argo (2013)