a minimal install xandros, which is based on debian etch. IceWM is indeed the default window manager.
But it has been tweaked by Asus, so, for example, MP3s play "out of the box", and there's the "Simple user interface", running on IceWM - that many eee users, including myself, have replaced with KDE.
I don't think you can (or should - there are licencing issues) install this exact distro (Xandros for the eee) on any other hardware, and I wonder why you would want to.
It all works perfectly for the eee, but I wouldn't choose it for my distro on any other hardware. In fact I am sorely tempted to install kubuntu on my eee, but the eee is my very portable computer, that "Just works", so perhaps I cannot be bothered to mess with it any more. I just use