Hmm it's not an inherently bad idea, but it's not very intuitive. config.ini wasn't intended to carry that kind of info. Plus I can see it being easy to futz up your config.ini whilst entering your groceries or whatever.

I would prefer a solution involving some kind of storage on one of the user partitions. Unfortunately that animal doesn't exist yet. Text files in some predetermined directory on the root partition would be another option, and like I said, I've almost written all of that code (though it uses the really slow GD graphics API for text.)