Next time you're feeling mischievous, try an "anti-Picardy third": end a major key piece (e.g. Pachelbel's Canon, US National Anthem, Silent Night, Happy Birthday...) with a minor chord.
When I was a kid I enjoyed annoying my parents by transposing random major-key songs into minor. I used to love doing this to "Joy to the World," among others, only to find later that the H.P. Lovecraft Historical Society had the same idea: https://www.youtube.com/watch?v=ptP0OR-e7rI.
There's a genre just starting where people electronically modify old recordings to change key. John Denver's Country Roads actually makes more sense in a minor key, to me at least:
