I can't remember the complete quote, but when you walk by one of the villagers midway through act one and he goes "There she goes again. If I weren't a married man I'd have her take me on an adventure" it always cracks me up.
That and almost every interaction between the Enchantress and Scoundrel is amazing.
There is a very rare dialog about Leah opening an Inn. Dont try to look for the dialog tho, its extremely rare and only a few people have ever heard it. You probably wont encounter it until a few months.
I've heard it twice IIRC.
She also does a call-back to it later, which I didn't understand on my first playthrough as I hadn't heard her first dialogue.