RAP4 GOLF Paintball Rounds
Yes, you read that right, GOLF Paintball rounds. While they do have a breakdown of the GOLF acronym, it's quite obvious that they were named after the shape of these new rounds. With tiny dimples covering each ball, they are designed to be more aerodynamic in flight.
The composition of these paintballs is also radically different, check this out:
I don't see powder fill balls ever being used for widespread recreational or commercial play, but an interesting design and implementation nonetheless.
Edit (Nov. 25th 2009): There will soon be a GOLF round available with a more traditional paintball fill. Also, it looks like Grey Ops will be able to take a look at these new rounds in the near future, so stay tuned!