I have never heard of this before. What is it, or, rather, where is it from?
Could you enchant a Spellbook to cast Make Whole or Mending at will?
Complete Arcane does have rules about making pages in a Spellbook out of metal, though I don't think they had this in mind; brilliant though.
The reason I ask is because I'm playing a character who writes and binds books on the side. As a gift to the party Wizard, a self-repairing Spellbook would be pretty cool.