Michael Westen:  Creating an explosive device in the field requires a strong knowledge of chemistry and the ability to improvise with whatever equipment happens to be lying around ... An old fire extinguisher makes an ideal compression chamber . Add some metal shavings and the right cleaning supplies , and you can serve up a bomb that can blast through a cinderblock wall .
Fiona Glenanne: Why is it you can never find a good sodium hydroxide solution when you need _ one _ ?