The EMP has become a standard weapon of choice for forces in a story that want to drive their target into a pre-technological state or at least significantly weaken them without an outright nuking. While many, many stories have an EMP in the mix, for some, the story as written could not exist without them.

Examples :

Dark Angel

Revolution TV Series

The off-screen backstory for Amerika

Jericho

Red Dawn Remake

Escape From LA, though as more of a threat that might come to pass.