Friday The 13th
Much to Hubs' chagrin, I tend to be very superstitious. I won't walk under ladders, I always have to knock on wood, and I almost never say never. Except in my world, Friday the 13th has always been a lucky day. I've had unexpected money show up, free lunches provided, extra fun movie dates with my spouse and all that treacly stuff. I love Fridays the 13th. They work well for me.
My bad luck day is, was, and always will be Mondays the 13th. Not only is "13" bad in and of itself, but Mondays always have their own special gruesomeness. So I'm stuck with hating on Mondays numbered 13.