Originally Posted by Petrus

Nope. Done correctly there will be very little mess. If you master the technique the bottle will cut perfectly without any shards or extreme spill.

If you study a champagne bottle you will there is a seam along the side. Sliding the knife/sword/whatever really will hit the weakest point of the bottle (on the neck, just below the foil), resulting the pressure plus a little force from the weapon popping the top off cleanly. The most critical part is that no one should be standing in front of the bottle for at least 20-30 feet as the thing flying is a small sharp missile.

It took me a couple of tries to master...