dwm
dwm is a dynamic window manager for X.
I use dwm on my Eee PC 701. It’s much easier to configure than most of its peers in the tiling window manager world, and is a blazing fast, keyboard-friendly pleasure to use.
Don’t be put off by the fact that you can only configure dwm by editing its source code—doing so is less bother than, say, endlessly fiddling with Compiz settings under Gnome—and installation is as simple as typing make clean install.
If anyone’s curious, here’s the lightly-modified dwm config.h I use.