Climbing gloves, being able to climb walls.
Hiking shoes, being able to run faster.
Flashlight, Pressing "F" will make your character flash brighter and repel certain enemies.
Happy mask, Acquiring this will make enemies smile. Smiling enemies tend to shoot less projectiles.
Broken typewriter, your character has a knack in repairing items. Only this hunk of junk is irrepairible. Slows your character down.
Good world wrench, press down on screws in the ground and you will tighten them, making bridges come down, or trapdoors open up.
Hover bracelets, press S and hold down and you will hover in air for three seconds. Let go of S to drop down. Use arrow keys to slowly navigate.
Flimsy balloon pack, Press B to bring out the balloon. You will start rising up and while doing so, gaining momentum. Hitting anything upwards will pop the balloon.
Bouncy shoes, press S to jump, and when you land press S and you will bounce off of the ground.