Never. I hardly ever type out "lol" anymore. It kind of annoys me now to a certian extent. I tend to use "lmao" more, but even then not so much so. When I first started chatting a few years back I used "lol" in nearly every sentance.
I was looking back at some emails from a friend from 2 years ago, and my message had so many "lol"'s in it... Ugh.