Item Duplication Glitch

First you need to place whatever item you want to dupe inside of a piggy bank or safe, break the piggy bank and just before you pick it back, yet still pick it up up exit the game. Since the piggy bank's on the floor, and in your inventory you duplicated whatever was inside and the piggy bank!

Worm Glitch

You will need any type of solid block and some worms. Put the worms and blocks next to each other in your hot bar, then switch their places. Exit and save your world. Go back into the same world with the same character then flip their places again. Exit and save and go back into the world and place the block on air and it will spawn worms.

100 Platinum Coin Glitch

You need 100 x dirt for this.

Place it in a piggy bank or safe then buy the dirt and save your world.

Leave your piggy bank or safe in the world and rejoin it.

Look in the safe or piggy bank and you will have a 99% chance of getting 50 to 1000 platinum coins!