Her thoughts were spinning in circles, like a rat chasing its tail.

Her mind began producing images in the darkness, images of rats chasing each other around the cavern, cireling iust beyond her reach.

For an example: the bit with the rat chasing the author is a fine and amusing idea, but it went on far too long.

Nightmares of dead Psychlos were intertwined with raw rats chasing mechanical horses that flew.

"When I came into camp that day, it was like a bunch of rats chasing the big cheese," Steinbrenner said.