Recently I saw this link lingering on Facebook, and yes it was about Kasargod Malayalam[A Wikipedia Page!], check it out Here. It lists out so many words, including the reasons for the slang, the Salient features, and the history! I never knew a slang had such details! Let me quote Wiki here -
Kasaragod Malayalam is very spontaneous and natural-sounding compared to the Malayalam that is spoken in South Kerala. The time taken to complete a sentence in Kasaragod Malayalam is nearly half that taken to complete the same sentence in the South Kerala dialect of Malayalam. Kasaragod Malayalam is deeply influenced and contains words from Tulu, Kannada, Arabic, Hindi, Tamil, etc. It is a very rapidly evolving language, adding new words into the language very frequently. The vocabulary of the language is so advanced that it provides single word substitutes for expressions even unavailable in the original Malayalam. Adaptation of vocabulary from various language helps the native speakers to learn and adapt to a new language with relatively low effort.
Here is a list of words found in Wikipedia -
Should admire the Writer! Kasrod Malayalam Rocks!
PS : You can find lots of funny videos on the slang in Youtube!