I'm sitting on my old desktop (450mhz) running an old Knoppix CD since the machine stopped booting. Things are unbelievably slow, but all I'm trying to do is organise my files so I'm surviving.
Anyway larswm is on this Knoppix CD and I've never really used it before but it is interesting. I haven't got into the tiling system yet to draw comparisons with ion but it does have a fairly neat feature where you can send the window to the top-left by pressing a combination + '7' on the keypad, or + '3' for bottom-right.. basically preset window locations can be selected and they're bound to the keypad in a logical way.
I did some tracing through PWM (which still holds a special place in my heart) to better understand how the MOTIF hints stuff works. Getting borderless windows working will be such a milestone for the WM..