Are there examples of cells with more than one nucleus?
Are there examples of cells with more than one nucleus?


Yes, they are called Multinucleate cells. There are two types of multinucleated cells


Syncytia
Coenocytes


I highly recommend having a look at this answer for the definitions.

Examples of Syncytia include


Osteoclasts
Skeletal muscle fibers (thanks @kmm)


Examples of Coenocytes include


Codium (Thanks @GerardoFurtado; see picture below)
Blastoderms early in the development of a fruit fly



  Are there examples of organisms with multiple nucleuses?


Side note: The plural of nucleus is nuclei

In many fungi, during sexual reproduction, a fusion of cytoplasm happen early in the mycelium but a fusion of the nucleus happens only very late (just before sporulation). This is a type of Coenocytic mycelium. In these species, non-negligible fractions of their cells are multinucleated.

There are endosymbiotic and endoparasitic eukaryotes in other eukaryotes that would result in a cell containing several nuclei but that would not count I would guess as the nuclei belong to different species.



Picture of Codium. The entire algea is a single multinucleated cell.