(It begins to look a little like #ifdef/#include, doesn't it? :)

My mind sort of wandered in this direction, and it would work for some of the problem, definitely. But I wouldn't want the username/passwords for the online demo in the source, obviously.

I've realized that my initial query was a bit unclear, and what I'm really asking is whether a single file could be diced up while 'Make'-ing a target to include the appropriate differences, i.e. EXP, LIVE, DEMO. Sorry about that.