* Simple and direct: The barista poured the coffee, leaving only the bitter dregs at the bottom of the pot.
* Figurative: The city's once vibrant arts scene had been reduced to the dregs of its former glory.
* Emphasizing unpleasantness: After a long night of revelry, the partygoers were left with nothing but the dregs of cheap beer and stale pizza.
* With a sense of history: The dusty, leather-bound book contained the dregs of a forgotten era.
The best sentence will depend on the context and what you want to emphasize about the dregs.