Question

which cells have more than one nucleus

Answer 1

they are called multinucleated or polynuclear cells and are eukaryotic in nature.
eg: muscle cells ,plasmodia, neutrophils and eosinophils etc..

Answer 2

 A Syncytia is a cell with more than one nucleus.
They are found in humans in the case of sicknesses like RSV, HIV, etc. Mitosis is NOT two nuclei - the nuclear envelope disappears during mitosis so the DNA is no longer in a nucleus! 
Some cells in the human body normally have more than one nucleus but this is kinda rare - liver cells, urinary system cells, parietal cells (of the stomach), chondrocytes, heart muscle cells can have more than one. 

Hope this may helps u............