Open Question: Methods of categorization, What are there?

[feedcrawler]

I'm looking to categorize the vast number of fetishes that exist, and ideally I'd like to explore all possibilities before deciding on one. One idea would be alphabetically, another might attempt to group them (i.e. Ones involving: Object (e.g. Underwear), Act (e.g. Spanking), Type (e.g. Tall), Area (/Partialism) (e.g. Feet) etc etc). Can you think of other methods of categorization? All suggestions welcome.

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