Hi Bob,
Yes, the program on Megalania was on "Into the Unknown" series on Discovery channel and Jeff Corwin did a brief segment on it, and Arthur C. Clarke back in early 1990's actually filmed such a giant Goanna on the Fly River, PNG - there are 'stories' throughout Indonesia/Malaysia of a giant varanid - I am actually writing a paper on stories on giant goannas and varanid worship around the World throughout history now....and Megalania was a big girl - she ate aborigines and marsupial giants too.
Rex gilroy wrote at length of sightings of megalania - and are of interest to read (however Rex is an admitted teller of tales and fibbed some of his findings in his books, so one must look to other accounts for the truth, and they become far less scant than before, but the stories persist. There is a report or two of a giant goanna in PNG, and most of the surrounding islands have specific tales of this animal. Maybe it is still alive? I'ld love to see one first-hand....
Cheers,
mbayless