[support] localization of currency, numbers etc...

I've to localise numbers, currency and dates accordingly to the chosen language. At this moment chosen language is just the one a user define in the profile.

Later it will be the one provided by the localisation (i18l or localizer [1]) module.

If I had complete control I'd add a function that read the current user settings and format numbers, date and currency accordingly... I didn't see anything like that in the api docs.

Do I really have to write such a beast? what would be the best place to put it so that is accessible from all over the site/modules/blocks?

thx

[1] What is the state of the art for localisation modules for 5.2?