The Terraria Inventory Editor makes it easy to start a new character from scratch if you like to just build things without needing to gather the materials, or if you are just impatient and want all the cool stuff now.
Download Latest Version Here: http://chbshoot.me/?page_id=100
If you are new to Terraria and haven’t yet “completed the game” without any cheats or hacks I would suggest staying away from this until you have beaten all the bosses, etc. otherwise this will just ruin the game for you. You have been warned.
Made by ‘Shoot’ on the KryptoDev Forum.
Forum Link: http://www.kryptodev.com/showthread.php?tid=12757
Edit: For a version 1.1 compatible inventory editor for Terraira try TerrariViewer: http://terrariviewer.codeplex.com/releases/view/71908
Final Edit: DO NOT USE AN OLD VERSION OF THIS, doing so will most likely cause you lose your character. I have removed the direct download link since I was not keeping it updated and people have been losing their characters. You’ve been warned!