standard on future models as well. Although the MI series sold well in Japan, it was never released in either the USA or Europe, and the Japanese user interface was never translated into any other language. The machines released outside Japan were the Linux based SL series, the first of which was the SL-5000D "developer edition". This was shortly followed by the SL-5500; both used 'Embedix' - an embedded version of the Linux operating system developed by Lineo - combined with Qtopia, the Qt toolkit-based embedded application environment developed by Trolltech. The development of the MI series in Japan was continued for a while, but the MI-E25DC has been officially declared to be the last MI-Series Zaurus. Sharp has continued development of the SL series in Japan releasing the SL-C700, C750, C760 and C860 models which all feature 640x480 VGA screen resolution. They are all based on faster 400 MHz Intel XScale technology, although the SL-C700 was flawed and the apparent speed was the same as the 206 MHz SL-5500. All four of the SL-C models are clamshell type devices with the unusual ability to rotate the screen. This allows the device to be used in landscape mode with the keyboard, much like a miniature notebook PC, or in portrait mode as a PDA. Sharp introduced a very different device from the clamshells in the form of the SL-6000 in early 2004; the SL-6000L (Wi-Fi only, no Bluetooth) was sold in North America, the last and only device since the 5xxx series to be officially sold outside Japan. It returned to the slider form of the 5xxx, but with a VGA display; a slider with a few key buttons covered a thumbboard. There was a joint project with IBM; the 6000 did not gain mass popularity and Amazon sold off their remaindered stock. In October 2004 Sharp announced the SL-C3000 - the world's first PDA with an integrated hard disk drive (preceding the Palm Life Drive). It featured a similar hardware and software specification to the earlier C860 model; the key differences were that it only had 16 MB of flash memory yet gained an internal 4 GB Hitachi microdrive, a USB Host port, and "lost" the serial port (in some cases the components were not fitted to the motherboard or were incapable of driving the regular serial adaptor cables). The keyboard feel and layout changed somewhat, and most owners