The zipper merges is the process that the flipping DEPARTMENT OF TRANSPORTATION tells you to do.  When a sign says merge ahead, wait until the merge point to change lanes.  USE BOTH LANES UP UNTIL THE MERGE TO PREVENT A BACK UP! 

People still argue against this, saying that traffic would flow better if everyone got in the right lane right away.  It has been proven wrong, and the zipper merge has been proven right with this video once again.

 

And then there is this knucklehead who thinks he's being a hero by backing up traffic trying to block the zipper merge.