I've teetered, and may still teeter, on an actual messiah complex. Thankfully I'm enough of a cognitivist to appreciate religion as canonical construct of existential algorithms, in effect, not to confuse the map with the territory, etc.
Another interesting psychological pattern of mine, is to interpret success along an axis, and seek out the extremity of that axis. I can try to think of better examples, but one was in freshman year where the axis was party-friendliness, and I chugged a water-bottle of bottom-tier vodka and woke up in the hospital. Or next year going sky-diving on LSD, etc.