I'm very curious: How do you use Anki for behavioural reminders (and what exactly do you mean by that?)

I'm a big fan of Anki's for language learning (I've studied some 4 or 5 languages with it already, and it went pretty well in all cases,) and I know many people use it for other things, but I haven't really seen something that would really captivate my interest besides language learning.