Known trinkets are as follows:
- ???'s Soul* - Provides a familiar that shoots homing spectral tears. Other familiars may follow him.
- Ace of Spades - Improves chances of finding cards
- Bloody Penny - 50% chance of dropping 1/2 heart upon picking up a coin
- Burnt Penny - 50% chance of (collectable) bomb spawning when picking up a coin
- Cain's Eye - 25% chance of Compass effect at the start of a floor
- Cancer - Doubles current tear stat
- Child's Heart -Increases the chance of receiving hearts from drops
- Counterfeit Penny - 50% chance of increasing coin value on pickup
- Cursed Skull - If Isaac's health is brought down to 1/2 of a heart, he is then teleported to a random room
- Curved Horn - Increase damage
- Eve's Bird Foot - Chance to spawn a Dead Bird when attacking an enemy
- Fish Head - Attack flies spawn every time Isaac gets hit
- Flat Penny - 50% chance of spawning a key when picking up a coin. May rarely spawn a golden key.
- Goat Hoof - Increases movement speed
- Isaac's Head - Provides a familiar which is similar to Brother Bobby, but with piercing tears
- Isaac's Fork - When clearing a room, provides a 10% chance of healing half a heart
- Judas's Tongue - Items in the devil room only cost 1 heart (only works if picked up before entering devil room, and items requiring soul hearts will still require 3 of them)
- The Left Hand - Replaces all normal and golden chests with red chests
- Liberty Cap - For each room, 25% chance to give Isaac a random passive mushroom-based effect. Can also give The Compass effect (cited as a bug on wiki).
- Lucky Toe - Increases chance of an item dropping after clearing a room
- Maggy's Faith - Gives an eternal heart at the start of each floor
- Match Stick - Increases bomb drop chance, can replace the Tick trinket.
- Missing page - 5% chance of invoking Necronomicon effect when receiving damage.
- Mom's Pearl - 10% chance of red hearts spawning as soul hearts instead (stacks with Mitre)
- Pinky Eye - 10% chance to fire a poison tear
- The Polaroid - If HP is half a heart, or receiving damage that would reduce HP to half a heart, Isaac receives a brief damage shield and HP is not reduced. Also allows entrance to "The Chest" when opening the big golden chest at the end of Cathedral.
- Push pin - 10% chance to fire a spectral tear
- Red Patch - Chance to activate the "Razor Blade" when hit
- Rusted Key - Improves key and golden key drop chance
- Safety Cap - Improves pill drop chance
- Samson's Lock - Chance of increasing damage when an enemy is killed for the current room (similar to Bloody Lust)
- Tick - Boss health decreased by 15%, 1 heart restored when entering a boss room. CannotCan only be replaced by Match Stick (be careful picking this up).
- Umbilical Cord - If brought to half a heart Little Steve will be spawned
Some info has been taken from The Binding of Isaac Wikia.