http://www.tinycorelinux.com/Tiny Core Linux is a very small (10 MB) minimal Linux Desktop. It is based on Linux 2.6 kernel, Busybox, Tiny X, Fltk, and Jwm. The core runs entirely in ram and boots very quickly.
It is not a complete desktop nor is all hardware completely supported. It represents only the core needed to boot into a very minimal X desktop typically with wired internet access.
The user has complete control over which applications and/or additional hardware to have supported, be it for a desktop, a nettop, an appliance, or server, selectable from our online repository.
Been playing with it this morning and it's super fast. You install the apps you want like Opera. I'm currently using it.