In 1997 and 1998 Robert Twigger staged two expeditions in Borneo and the Spice Islands searching for the world's longest snake.
He also discovered a previously unrecorded line of menhirs (megalithic standing stones) stretching across North Borneo into Kalimantan.
The book of the expedition, first published by Gollancz, is available on Amazon entitled Big Snake.
There is also a National Geographic/Channel 4 film presented by Robert also called Big Snake which can be watched on the Channel 4 site. Big Snake Film - Channel 4