I just had the idea that it would be cool to have a hex editor that would allow loading a list of single (or maybe double?) byte addresses from a file. Preferably, each address would have a field to add a comment (explaining what they are). The hex would have an interface that would display the loaded list with comments and that would allow easy change of value for each address and then saving the loaded file (ROM). Is there already such a tool? I have found a series of addresses for a game that refer to weapon damage, character health, etc, and it'd be neat to have a handy editor for when beta testing the hack. I feel like this would speed up the testing process.
edit: I imagine this would be almost like a patcher... You load a list of preset modifications, modify their values and then you can use it to patch a ROM file. Or you can load the list of addresses and a ROM file and it will show the default values for those addresses before you change them.
edit2: I think "cheat patcher" http://www.romhacking.net/utilities/1112/
is very close to what I was looking for. I'll be testing that.