It's been 20 years since the legendary nightclub Studio 54 opened its closely guarded doors, but disco fever is hot again. A new bbook documenting the rise and fall of Studio 54 called The Last Party (William Morrow) by Anthony-Haden Guest and an accompanying exhibition, "The Last Party: Nightworld in Photographs," at the Serge Sorokko Gallery in New York are stoking the fires. It's history with a dance beat.