Fireproof Carbon Foam

[LockH]

... from Pyrolysed Bread. (Thinking battery cells protection here.)

Carbon foam has some very useful properties: It is an excellent thermal insulator.
The fact that it's made from bread adds "much wow!" to a very simple process.
You could conceivably cover you space rocket in these ablative tiles for re-entry.

Seen as DIY here:
http://www.instructables.com/id/Fireproof-Carbon-Foam-From-Pyrolysed-Bread/