The Reptiles

Nordics
Supposed to peaceful and foes of the evil grey ones, but apparently they like to abduct humans as well and talk their ears off while feeding them heavy fatty foods.

Rigelians of Rigel 4

Existing only within "The Simpsons" Universe, Kodos & Kang visit Earth every Halloween. Once even Serak the Preparer visited during an abudction of the Simpson family. Marge: "You speak English." Kang: "I am actually speaking Rigelian. By an astonishing coincidence, both of our languages are exactly the same."