I can't see many people missing that (at least if they have to press fn-shift first anyway) :-).
I don't know how the keymapping is handled (but I can't see any troubles with having this one mapping to £, I just don't know how though), but it might also be worth looking at one of those add on programs which do foreign keymappings - actually OZ comes with something which does this (I can currently change the language to Czech I think), I wonder if it's a simple case of altering a conf file somewhere to specify which keys map to which symbols/chars for a given language.
Anyone?
Si