I just came across this animal while reading an article. It's called the "Giant Coconut Crab", and the name is very appropriate.
It's a crab, it can crack open coconuts, and... yes, it's gigantic!
Here's a link to some more images and videos of them in action. All I can say is HOLY COW! They may be harmless to humans, but I'd hate to wake up with one of them in my lap.
"C'mere! Gimme yer wallet!"