Ethnic

Non-Italian food in Naples?  Yes, there are indeed a few places:

Sushi/Japanese

• • Jap One Sushi Bar - near Piazza dei Martiri, probably the best sushi in town but also the most expensive; rec'd by Gambero Rosso, L'Espresso, and Carla Capalbo.

  • Tokyo - near Piedigrotta/Mergellina, 40°49.96'N 14°13.46'E, popular sushi place with Americans, one of the best values (especially their huge sushi boats); it used to be a Chinese place called L'Acquario, see blog review.   www.ristorantegiapponesetokyo.com 

  • Zen2 - just south of Piazza Dante, another good sushi place, similar to Tokyo but a bit smaller, www.sitoflash.it/zen2/

  • Kukai - near Plebiscito, a bit fancier than Tokyo/Zen2 but not as expensive as Jap One, they also deliver to the Posillipo/Vomero area; www.kukai.it

• La Garconne - "Harem-style sushi bar/discoteque" www.lagarconne.it

• Il Sushivendolo - near Piedigrotta/Mergellina, take-away sushi, www.sushivendolo.it

• Nereis - along the water, just north of downtown Baia, "sushi bar" every Thursday starting at 9, www.nereis.it

• Nero Sushi - along the water in "Santa Lucia" neighborhood near Castel dell'Ovo, www.nerosushi.it, a newcomer on the waterfront, also features a takeout/delivery menu.

• Sushi @ Pozzuoli - Japanese woman who lives in Pozzuoli will make sushi to order, given at least 2 days' notice; sushi-at-pozzuoli.blogspot.com

Spanish, Mexican, and South American

• • Mexican: Mamacitas - Caserta, GPS 41.08243N 14.34974E, behind Birreria del Re Restaurant www.mamacitas.it, also see locali caserta.

  • Mexican: El Moccolo - Naples (S of the Amadeo metro near Villa Comunale), www.ilmoccolo.it, info@ilmoccolo.it

  • Spanish/Mexican: El Sangrero - Giugliano In Campania/Licola, near disco "Impero 2" and pizzeria "La Chamade", see blog review (in Italian)

  • Spanish/Venezuelan: El Bocadillo near Piazza Amadeo, www.elbocadillo.it, closed Sat/Sun (Spanish?)

• Spanish (?): El Muerzo - via Giovanni Bausan (downhill from Amadeo near Riviera Chiaia)

• Argentinian/South American: La Cueva near Piazza Amadeo, www.lacuevanapoli.it

• Brazilian: Porta Ventosa near University, closed Sun.

• Brazilian Barbeque: Churrà; from the Tang, turn left off Varcaturo exit, www.churra.it, they keep bringing skewers of barbecued meat until you can't eat anymore, all for ~€35

• South American:  Il Picaro - near Piazza Amadeo, "trendy"

• Spanish: La Casa Basca - Posilipo, only dinner, closed Sun

• El Payaro - Vomero

• Yes Brazil - Posillipo

• Cuban: Puerta Libre - Capua, www.puerto-libre.net

• NOT Mexican (fixed price ~€40/person seafood restaurant, not sure why it's called "the Mexican"): "Il Messicano"  in Bacoli

Chinese

• • Xin Da (Sas di Chen Guojie), Arco Felice - not bad but nothing to write home about.

  • Il Drago d'Oro - (near via Toledo), mostly Shanghai dishes, see old review.

  • Asia Di Qin Hong - (near via Toledo), mostly Cantonese, see old review.

• Peking - Chiaia 

• Shangai Li/Di Boccia Antonio - Bagnoli/Fuorigrotta - supposedly not very good

• Shanghai Restaurant Aversa - Aversa, 40°58.782'N 14°12.711'E,  menu and brochure

• Ristorante Cinese Shang Hai Lago Patria - Castel Volturno

• [another one in Teverola?]

Other Asian

• Thai/Vietnamese/Sri Lankan/Indian - New Asian Restaurant, near Castel Capuano

• Thai/Chinese - La Muraglia, near University/Port near Piazza Borsa, via Giulio Cesare Cortese 8

• Thai/Chinese: Ristorante Giada - right by Piazza Plebiscito, decent Thai food in a convenient location

Greek

• • Zorbas - near Piazza Amadeo, closed Mon

  • [another one near Amadeo?  one in Vomero on via Caravaggio??]

Other

• Arab: Amir - near S Chiara?

• Eritrean: Mar Rosso - N of Piazza del Plebiscito, see Stars & Stripes article

Also see Italian Yahoo Answer page, Eristorante.com, Corriere del Mezzogiorno, and Ciao.it opinions (all in Italian)