Thanks for the suggestions! If I do go ahead with using the data directory I think I'll try Dan's idea of a folder with the frankenstyle name of the plugin, but thinking about David's question made me realise the database probably is an appropriate place for it. I'm kind of reluctant to create a database table just to cache some data that is always accessed as a single entity, though, but I should probably just go ahead and do that anyway.
General developer forum
Where to put files in data directory?
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