Many think that both Guru Dutt and Shyam Benegal are Bongs (Bengalis). Guru Dutt perhaps because his surname was replaced by his new name Dutt which is also a Bengali surname and Benegal because perhaps because he's related to Guru Dutt and his surname as I have heard many say, 'sounds Bengali'.
The relatively small speaking community of Chitrapur Saraswats have given many a luminaries across various walks of life. Former Infy CEO Nandan Nilekani is another name we should not miss on...
CSB's like the Gaud Saraswats (or the GSB's), and Rajapur Saraswats are Konkani speaking and have their cultural roots in Gomantak or Goa. The Saraswats migrated to the southern states during the post medieval period persecution by the Portuguese. These communities have still retained their distinct traditions, language, and cuisine.