Huge thanks to Eleanor and John Bannick of 7-128.com for re-pointing me to Camera Mouse. I was aware of this back in 2007, tried it, and I think duly forgot about it as it didn't work too brilliantly for me.
Well, I'm guessing some significant updates (and me having a better computer) have turned this into an absolutely brilliant utility. So simple to use from the go and effective. I'm very curious to see how well it works on top of the likes of Alt-Controller. Free as well.
Added to the Accessible Gaming Shop: Head, Mouth and Eye Control section.