7. Explosive Gel
In Batman: Its one of Batmans most reached for gadgets in the Rocksteady Arkham games, used for all manner of tasks from exploding down destroyable walls to incapacitating unwary henchmen.
In Reality: Its a form of demolition blasting explosive known as a Water Gel Explosive, the prime ingredient of which is Monomethylamine Nitrate made up of MMA, fromaldehyde and ammonium nitrate. It's then usually stored ready for use in straw-like packaging, like so:
The long and short of it is that process used to produce this substance yields an explosive liquid, which can then be thickened into any consistency using a gelatinizing agent. End result? Plausible Bat-Explosive Gel. Awesome. But just saying you can own something, for your own sake, doesnt mean you should.