What did you do! Whyy??
I made a small module which is just meant to store user preferences. There's the normal-ish approach of using a field on either the User entity or the Profile entity but in all honesty this can get messy when you add one ...then another one. Oh god the client wants more user options. Soo you get it.
Drupal 6 veterans, remember the fun times of
$user->data, the mad grab wild west of "here's an array, do what you will" which also exists in D7.
User preferences was created to solve this problem, taking a proper approach at storing user preferences which don't require you to regret slapping another field on an entity or crying in the shower scrubbing yourself after using
There's work to do around the schema and looking at how to best store different types of values in the Database (currently just string), but this module is a first good step. Some tests need writing too, patches welcome!
Anyway, that's it for now. Stable release coming soon after some testing.