These Giant Robot Battle Fists from ThinkGeek are all kinds of awesome:

• Forged from the Cobalt Flame and Robotonium
• Wield to defend your city from evil in all its forms
• Inflatable, comfortable, and awesome
• Intended only for protecting cities and fighting monsters, not for battling friends or use as a flotation device.
• Includes: 2 inflatable fists
• You must provide: air