There are currently 24 contiguous bytes of unused space in the SQLite header. If need be, and if SQLite catches on for use as a portable image format, I will be willing to allocate some or all of those 24 bytes to an identifier string for file(1).
If you would be willing, what's your opinion on using SQLite as an image format like this? The "When to Use" page specifically sites application file formats as a good use, but would your header byte allocation be done begrudgingly or contentedly?