Another vote for fvwm. I've customized it pretty heavily over the years:

I have a single config file that detects which host its running on and modifies fvwm's behavior accordingly. This way I can have the same configuration work well on the desktop and the netbook.

It works well on the netbook, too, as its very resource-friendly.

I have it set up with a 3x3 virtual desktop space and no edge resistance. The "Windows" key pops up the virtual desktop manager.

Also, I have it configured so that when I hit the "Menu" key or CTRL-Windows I get the root menu, so it's reasonably keyboard friendly. (e.g. CTRL-Windows,T gets me a terminal; CTRL-Windows,N,W gives a browser.)

Not that I use those, really, since I have F1 on the root window bound to "launch terminal", and F2 to "launch browser".

FVMW doesn't work as well as others out-of-the-box, but you can pretty much make it do anything if you tweak the config enough. But that's work, so you gotta wannit.

I really wish it was a compositing window manager, but it's not, and it doesn't seem likely to be.