[Brian_K_White]

I think the only thing that will ever really make sense is flat horizontal property lists.

A given item and a given transaction could have any number of different properties, and no single heirachical category can express the reality.

Is it a work expense or is paid through paypal or is it a subscription or is it from amazon or is it food? A single item could be all of those at once, and sometimes when you want to know "all food" you want to include that regardless what it's other properties are.

IE, pork doesn't really have to be under some heirarchy like meat. It is both pork and meat, and it also may be art supplies or photographic subject etc.