There had been many proprietary PDA/appliances based on ARM. Although Sharp discontinued the whole product line, many Linux enthusiasms have been inspired to port Linux on other devices during the community project gets great success. A couple of projects are derived from it. Supported platform expanded to MIPS, PowerPC and others. There are a lot of really interesting applications among those projects. However, if a specific product isn’t available for Linux at the beginning, the technology evolve may not happen.