Originally Posted by ATDrake
Based on this, I suggest trying holidays/holiday aftermath long weekends, and Sundays. Friday is not too bad (end of work/school week when the load tends to lighten up a bit; people want to relax a bit before gearing up for the weekend), but it, like Saturday, tend to be days when people tend to have other entertainment plans scheduled which may not involve surfing the internet.
Sounds pretty well-reasoned, and matches my limited experience as well. I'm contemplating either the 26th, 27th or 30th right now for my last freebie of the year.