When performed correctly, as noted above on a suitably chilled bottle of Champagne, the cork and glass ring will fly away, spilling little of the precious wine and leaves a neat cut on the neck of the bottle. Now, the Champagne is ready to be enjoyed. Not to worry, the internal pressure (100 psi) of the Champagne bottle always ensures that no glass falls back into the bottle making it safe for consumption.
If you do try this, let us know how it turns out! Link -via the Presurfer