Just a quick addendum to the story about the Bornean slugs slugging it out with their snaily prey. The same group of slugs, Rathouisiidae, also occurs in north-eastern Australia. I've uncovered them while looking for earthworms in what passes for soil in tropical rainforests.
They're amazing animals. They're only a few centrimetres long and triangular in cross section. While they're happy, they look pretty sluggy. But annoy one (by picking it up or speaking about it in a derogatory fashion) and it will go dry and hard like a piece of twig.
Rathouisiids are largely carnivorous. Like other predatory land molluscs, their multiple teeth are shaped like sabres and can shred soft tissue. When not annoyed, the slugs are very active. Flag-like flaps wave around the mouth as a slug searches for prey on the forest floor. The flaps may have a sensory function, locating food by scent or touch.
Who needs charismatic megafauna when we've got wonders like these?