The Audiobendr amplifier is going to help you pump up the volume of your phone in a way that hasn't really been done. There have been phone amps before, but none so small, made of rubber and waterproof. The amplifier, isn't even a technological innovation, as it doesn't use wires or anything else; it just takes the sound, bends it through a small hoop and pumps is up.
Rather than lugging around a big box amplifier that will weigh you down, you can opt for the Audiobendr. When it's not in use, it simply hooks onto your keychain, making for a colorful addition to the chain of key rings that you already have.