My pc don't have multimedia keys...
fn+F3 (toogles Touchpad) on Asus eee 1005P turns Touchpad off, but cannot turn it back on again. Touchpad is still disabled after reboot.
Toshiba A70 audio hotkeys appear to have no effect (these have never worked under Ubuntu AFAIK but did under XP).
Note that Fn-hotkeys like brightness work.
WWW key doesn't work. Firefox doesn't appear while pressing WWW key.