[sfrailsdev]

you don't even have to go to non english, just utf-8 has stuff like mathematic spaces and spaces of different em sizes. http://perldoc.perl.org/perlrecharclass.html has a reasonably good list of non ascii spaces, though I'm not sure where to dig through for locale specific lists.

That said, while it may not be a solution for every case, it's a solution for the common case and a starting point for other cases, and thus pretty nifty and potentially useful.