I own one of the great miracles of the modern age -- a filter pitcher. While this has made my life much more enjoyable, there's a flaw inherent in the design of the pitcher I have.
The problem is the filter insert seals the top of the pitcher, except for the spout. This is fine, until you try to pour at full tilt. When water leaves the pitcher through the spout, a vacuum is formed inside and air is sucked back in. Pouring is slow and uneven when this happens.
Demonstration
We can fix this by adding a vent. A small hole drilled into the back of the pitcher allows air to enter and the pitcher to empty
faster.
Brita Slim Filter Pitcher
Fix what's broken.
Update: I've received many comments about the orientation of the insert. When in the "proper" orientation, the insert wants to come off with the cover when opened and then blocks part of the spout. I use the tab now to hold the insert in.