One of my favorite Bruce Smith memories is Jeff George dropping back, looking left, and clearly mouthing bug-eyed "Oh, *****!" before Smith annihilates him for the fourth time that game.
And one of my favorite SB XXV moments is captured in the series of stills where Leon Seals pancakes Hostetler.
One of the reasons sacks aren't as important nowadays is because that level of intimidation has been taken out of the pass rush. QBs are much more protected nowadays, so you don't see "pressures" where the QB is pancaked after the throw, or where QBs are honestly frightened at the prospect of being sacked. Getting a QB rattled has become less about the intimidation, and more about getting inside the QBs decision cycle and forcing errors.
That being said, they're not unimportant, either. A mere "pressure" never turned a 2nd and 5 into a 3rd and 18 (intentional grounding excepted, which frankly should be tracked as a stat along with sacks) and drastically limited an offense's play calling options.