Luck: I won a pair of 7up boxers in a second-chance drawing when I was 16. The odd free Mt. Dew when they used to do those instant win caps (you could turn the bottle to the side and tell if you had an instant win or not; I think I chained like five or six free bottles doing that.)
Skill: Uh... again, when I was 16, I led our high school quiz bowl team to regional champs.
I won that Bayonetta gun from SEGA’s Twitter giveaways. (I may be getting closer to having the ability to sell it, in case the person who wanted to buy it still lurks 'round these parts.)
When the little annual fair near my house wasn't just a bingo hall with a dirty inflatable slide, I'd make a point of winning a knife and a bottle of soda each year in the ring toss games. Got pretty good at it, too.