Final Fantasy XII

Unlockable Fishing Spots:

Middle Reaches - Get 5 perfect fishing in the Lower Reaches
Upper Reaches - Get 5 perfect fishing in the Middle Reaches
Secret Reaches - Fish up Cactoid Bond in the Upper Reaches with Matamune
Master Den - Fish up Cactoid Crest un the Secret Reaches
Taikou Chest (treasure) - Get 9 perfect fishing in the Master Den

Sky Pirate's Den Figurines:

Trickster - Awarded for defeating the monster, Trickster.
King Behemoth - Awarded for defeating the monster, King Behemoth.
Gilgamesh - Awarded for defeating the monster, Gilgamesh.
Zodiac - Awarded for defeating the esper, Zodiac.
Yazmat - Awarded for defeating the monster, Yazmat.
Carrot - Awarded for defeating the monster, Carrot.
Fafnir - Awarded for defeating the monster, Fafnir.
Hell Wyrm - Awarded for defeating the monster, Devil Dragon.
Ultima - Awarded for defeating the esper, Ultima.
DeathGaze - Awarded for defeating the monster, Death Gaze.
Fran - Awarded for using magic 200 times.
Balthier -Awarded for attacking 300 times.
Ashe - Awarded for having the average party level over 50.
Basch - Awarded for killing 500 foes.
Penelo - Awarded for getting 100,000 gil.
Vayne - Awarded for using techniques 100 times.
Montblanc - Awarded for attaining (monster) chain level 50.
Gurdy - Awarded for using/spending 1,000,000 gil.
Chocobo - Awarded for walking 50,000 steps.
Migelo - Awarded for selling 1000 loot.
Dalan - Awarded for completing every map.
Reks - Awarded for earning 500,000 clan points.
Gabranth - Awarded for initiating every fusion technique.
Ba'Gamnan - Awarded for completing the hunt catalog.
Vossler - Awarded for obtaining every character's techniques.
Crystal - Awarded for obtaining every character's magics.
Belias - Awarded for obtaining every esper.
Vaan - Awarded for stealing 50 times from enemies.
Rasler - Awarded for mastering all character's license board.
Mimic? - Unlock and buy all Monographs and Canopic Jar, also create and buy several Bazaar items to unlock.

Obtaining the Zodiac Spear:

These four places contain treasure chests that must not be opened:

1) Treasure chest in Lowtown, outside of Old Dalan's place
2) When sneaking into the palace (Before getting the Goddess Tear), there are several chests in the Cellar. Do not open the two chests in the southeast corner.
3) All treasure chests in the Confiscatory (the place where you get your weapons and armor back after being captured)
4) In the Phon Coast, later in the game, there is an island with 16 chests all near each other. The 4th chest that must NOT be opened is among these, so it is best to leave them all alone. They only contain Gil anyway.

If you've left all these treasures alone, you'll find the Zodiac Spear in the Necrohol of Nabudis.