The Tech21 iBand case for the iPhone 3G and iPhone 3GS is constructed from an intelligent material called d3o which can transforms a flexible, soft gel into a shock resistant casing on impact and has been featured on Dragons Den.
When at rest, the d3o material stays soft and flexible, but if dropped the free flowing molecules in d3o form together to absorb the impact and thus safeguard your iPhone handset, and when back at rest the iBand returns to soft and flexible.
Tech21 iBand case for the iPhone 3G and iPhone 3GS allows full access to iPhone controls and connectors, and is available via eXpansys commanding a price tag of £14.99.