The phrase "Nantucket nightlife" verges on an oxymoron -- and, during the off-season, it's virtually a nonentity. If it's glitz and nonstop action you're after, better stick to the mainland. On the other hand, if you like live music, you will never go lacking -- at least in season.
For listings of events, see the Inquirer and Mirror (www.ack.net), the Nantucket Independent (www.nantucketindependent.com), and (in season) Yesterday's Island (www.yesterdaysisland.com); the latter two are distributed free. Posters around town announce coming attractions: check the board outside the Hub, a newsstand at the corner of Federal and Main streets.