OB is the most severe penalty, and therefore intimidating, but I have never come across a hole with OB on both sides of the fairway.
Gorse, as a hazard, is similar to OB--if you hit it in gorse off the tee, you might as well tee up another. And I have played holes with gorse lining both sides of the fairway and to me they are the most intimidating of all tee shots. Examples include the 7th at Dornoch (and I've heard it used to be even narrower) and the 6th on the New Course at St. Andrews. When played in any type of wind, keeping your tee shot between those remorseless thorns is a difficult and intimidating proposition.
While writing this, I've thought of an example which combines the two--the 11th at Troon, one of the hardest tee shots I've ever had to play.