The most obvious task when making any application multi-lingual is to make the UI translatable; there are absolutely tons of options for this, libraries in all sorts of languages, recipes, discussions, etc. But for many applications there’s another task, just as important, which is taking a database, and allowing someone to translate the data inside that.
There are various approaches to “database i18n” too – generally involving re-designing your schema in such a way that the translations are to some extent part of the “normalised” data. But these tend to make the schema somewhat unwieldy, and writing ad hoc queries and reports becomes tricky. So it occurred to me that if you treat i18n not as a schema problem, but as a data type problem, you could save some of that pain.