I think carrying 3 season passes automatically qualifies, but the surest sign of my skiing insanity is...
the spreadsheet I have maintained for almost 20 years now. I track almost everything across all of the my equipment (including my clothing choices for different weather). I measure and calculate numerous ski characteristics including actual chord length vs. base length, calculated sidecut vs. published, tip cut and tail cut, overall taper, effective edge, running length (CRS), and surface area. For my boots I track the setups for numerous pairs of boots; including the weight of the entire boot, shell, liner, and bootboards. I measure the forward lean, canting angles, net ramp, bootboard ramp, height of the bootboards at the heel and toe, and finally the height of the heel and toe lugs. Then there's the measurements and calculations of binding delta and binding mount positions of all of the skis I have owned over the years.
Oh, and I have a database of the specs for thousands of skis I've updated for over 20 years.
I also track all my ski days; including total vertical, # of runs, daily conditions, and avg/max speed.