Microsoft Visual Studio comes with an excellent XML editor. By far, the most useful feature is that it can read an XSD file and know exactly how your XML is supposed to be structured (the only other XML editor I know of that can do this will set you back $500). This means that, for the most part, you don't have to memorize tag names, what tags can go where, attribute names, and in many circumstances, attribute values. As soon as you type the opening bracket, it will provide you with a drop-down list of all available tags that are legal given your current position in the code. Once you select a tag and hit space, you'll be presented with a list of all possible attributes for the tag. Select one, and if it's not a free-form value (like name, or val) it will present you with a list of all pos