As the topic of this game states, what games do you own that have the best replay value.
Then we hit the best and worst unlockables, which like they say , are the best unlockables that you know of and the worst of the same caliber.

For those that don't know.
Example : Something Something X
Good replay value, because of an extra dungeon and non-repeating themes in the second story.

Example: Something Something Y
Horrid replay value, only hidden unlockable is a hat that does'nt even grant any powers or anything. It's just there after putting in 40 hours of gameplay and beating the game on all the difficulties.

Best Replay Values

Illbleed, two optional paths down the story
Siren, the game's not done when you finish it the first time AND it requires you to find all the files to unlock the true "Intro" of the game
Final Fantasy X-2, the only final fantasy I've beaten more than twice because I wanted to .
Star Ocean 2, 40 endings? Hidden Dungeon? Super hidden items that require hard work?
Silent Hill 2, 5 Endings,two of which are hard as hell to get , Maria and in the water endings .. Talk about being picky

Worst Replay Value

Dark Cloud 2, sitting through those never ending dungons once was bad enough. I could'nt take another romp through the forests , dash through the mountains or bother rebuilding the same town to perfection once more

Beyond Good or Evil, it wrapped up way to fast and it tends to become boring untill you reach the instant death parts

XIII, talk about leaving a person hanging .. .

Digimon World 2, you already sat through it once, why bother a second time?

God of War, a person can only take so much.

Everyones' favorite topic!

Best Unlockables

Viewtiful Joe PS2 edition. Although I don't like Dante all that much, the ability to fight fire with fire is nice.

Star Ocean 3, a claude costume? Oh my.

Deception , one word "Suezo"

Illbleed, nothing like jumping rope while you're half naked.

Manhunt, the ability to become invisible and not heard at all, although an unlockable to make enemies spawn endlessly would be nice as well.

WORST unlockables.

Nightshade, so you manage to complete the game on the highest setting, what do you get? A crappy costume of her , with a banjo or guitar or something as a sword.

Syphon Filter The Omega Strain, not really that bad but to get most of the unlockables you MUST play online or use a cheat device.

Omnimusha 2, the man in black bonus game. I've never seen such an nice idea on a surivial mode butchered since Rising Zan Samurai Gunman. O o

King of Fighters 2001, defeat 200 people in party mode to unlock Igniz whatever.It's not hard to do if you can manage to stay awake that long.

Any game that rewards any type of "Special outfit" that is nothing more than the normal outfit just with a color swap for beating the game on hard or higher without adding any real bonus to it.

I would say any game that offers no unlockables and no replay value, but those are marked under bad games.