Want to build an epic house in creative mode and offer the download as survival, or maybe you want to make a cool RPG or adventure map and not have to tear up the countryside looking for materials? There are plenty of item mods out there that let you free build in survival mode, but some of you don't know how to install mods( if you guys want me to make a vid on modding let me know) and most mods break after a Minecraft update so you are stuck waiting for the mod itself to update and remodding your entire .jar file. Well Notch solved the problem for you, all you have to do is use Creative Mode to build and then switch that save to Survival. It is fast and easy and can be done in a few easy steps.
First, I am assuming you have some type of tool to unzip/unrar files if not go here and download and install (this is a tool you will need for almost everything you download from the internet).
Next go here and download NBTedit and place that on your desktop.
now for the fun, make a folder (right click on desktop choose new and folder) name it minecraft and put it where you like, we will keep it on the desktop to make it easy. Usually most tutorials ask you to hit the start button go to the search programs and files bar and type %appdata% and click roaming to find your .minecraft folder, I hate that and this will be your last time doing it, when you get to your .minecraft folder right click and drag it to your desktop let go and choose create shortcut here, put that in your new minecraft folder and now anytime you want to access .minecraft just double click the shortcut! next right click the NBTedit file and choose extract to NBTedit, you should have a new folder called NBTedit place that in your minecraft folder, now on your desktop you should have a minecraft folder containing your .minecraft shortcut and NBTedit folder if not you missed a step. now start Minecraft and use Creative mode to build anything, name the world something that will be easy to find, we will call ours weenyroast. Now lets get acquainted with the .minecraft folder, open your minecraft folder on your desktop and double click your .minecraft shortcut, inside locate the saves folder, inside there locate your new save ie. weenyroast and open that, locate level.dat that is the file we will work with, close everything. Ok we have made it to the money shot! Open your minecraft folder (desktop) and go to your NBTedit folder click NBTedit a window will open, click "file" on the upper left then choose "open" another window will open, on the left choose desktop then our minecraft folder open that and open our .mincraft shortcut open that go to saves and open the weenyroast folder and finally click and open the level.dat file whew! The window should now show a plus sign with Data: a number of entries click the plus sign, double Click GameType change type to 1 for creative (0 for survival) and hit enter then go back to "file" and choose "save". You are done! you can swich any of your saves by using this method have fun!