I mean, I assume MMOs don't count for this, because I put a couple hours into FFXIV almost every night, so that's more of a "habit" than a binge.

Last time I had a good binge though? I have to save them for when I'm either on vacation, or playing something for the sake of writing a review. In that regard, I suppose my last binge was Lightning Returns. Before that though, I'm pretty sure I dumped dozens of hours into Dragon's Dogma. I'm still only one trophy away from a platinum and I reeeeeeally need to go back to that at some point soon to finish it up.

And for what it's worth, I full-complete FFVI at least twice a year, and usually do it within a week or two every time, split into decent chunks between other things.