Malapascua Island

Malapascua Island 
It's a small island to the north of Cebu in the Philippines.
Why do you care?  Because diving with Thresher Sharks.
About 20 mins boat ride from the island is Monad Shoal, a Thresher shark cleaning station where you are almost guaranteed to see these great majestic beauties.
Slight catch: you do need to go at about 5:00am to see them.  But man is it worth it.
Don't believe me?  Check out this video.

The dives go like this.  After getting up early (ouch) and motoring to the dive site, you will descend with a guide and small group to about 25 - 30 meters where your guide will look for the Threshers.  If you are lucky you will kneel there in the sand while they circle around you.  It is truly beautiful!
Nitrox is highly recommended for these dives, because you'll eat up your no-deco time quickly sitting at 30m on air.  And you want to maximise your time with these guys.
Need some new gear?  Check out JustLooking for some good deals on gear.
Plan on doing 3 or 4 of these early morning trips on your visit.
​Also worth noting: the food on this island is awesome!