This level of customization is not possible with the Xandros system. On the Eee, you'd have to install a different Linux distro. gOS and Dreamlinux are two Linux distributions that offer a similar user interface to Mac OS X. Because gOS is built for low-power devices like the Eee, it should work well. Dreamlinux isn't specifically designed for the Eee, although it does have a low system requirement.
Linux is a group of open-source Unix-like operating systems based on Linus Torvalds' Linux kernel, which was initially released on September 17, 1991. Linux is commonly packaged as part of a Linux distribution.
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