Copypasting from http://board.byuu.org/viewtopic.php?f=9&t=1804:

http://byuusan.kuro-hitsuji.net/solar-magic/sm100.zip

Solar Magic is a launcher that extends Lunar Magic to fully support headerless ROMs.

Solar Magic
Version 1.00
Author: byuu
Release date: 2011-07-09

About:
The original Lunar Magic application requires a header to be appended before it can edit the files.
By using Solar Magic, headerless ROMs can be opened and edited directly, without the need for a header to ever be appended.
Unlike simple batch scripts, Solar Magic will not simply create hidden copies of the file.
It truly extends Lunar Magic to seamlessly support headerless ROMs.

Support:
Permission was granted by FuSoYa to make this application.
However, there is absolutely no support provided by FuSoYa for this application.
Please do not contact FuSoYa about Solar Magic.

[bTechnical details:
Solar Magic.exe is a launcher application. It will load in Lunar Magic.dll as a new debuggee process.
It will then overwrite the program entry point to perform a DLL injection for Solar Magic.dll.
Once Solar Magic.dll is loaded into the process, it will hook all file access functions from the process' copy of kernel32.
The original entry point for Lunar Magic will then be restored, and the program will be allowed to run normally.
Command-line arguments are forwarded along, so drag-and-drop still works seamlessly.
When Lunar Magic attempts to work with SNES ROM images, Solar Magic will intervene.
If it detects a headerless ROM, it will tell Lunar Magic that there is indeed a header, and adjust the ROM offsets to compensate.
If it detects a headered ROM, operation will be identical to the standard Lunar Magic.
The entire process is 100% seamless and transparent. Absolutely no modifications have been made to the Lunar Magic binary.
The Lunar Magic binary was simply renamed to a DLL so that it is not accidentally launched instead of Solar Magic.

Extensibility:
Full source code is provided for reference.
Both previous and future versions of Lunar Magic should be fully compatible with Solar Magic.
In fact, the technique is easily extensive to virtually any Windows application that does not support headerless ROMs.

____________________
Wife make lunch - Shampoo
Opera - give it a spin
Spare some of your free time?
<GreyMaria> I walked around the Lake so many goddamn times that my sex drive was brutally murdered
Kawa rocks — byuu

Solar Magic has been renamed Header Magic because of conflicts with Solar Magic Advanced. That'll be all.

____________________
Wife make lunch - Shampoo
Opera - give it a spin
Spare some of your free time?
<GreyMaria> I walked around the Lake so many goddamn times that my sex drive was brutally murdered
Kawa rocks — byuu