Major or Minor?

I've been thinking this over lately, and I have a new songwriting goal. That is: Write a sad song in major, and a happy song in minor. For those of you who don't know, major generally sounds happy, and minor usually sounds sad. That's the easiest way to explain it. Well, it's easier than saying that the minor triad is built of it's relative major's 6th. Although if you understand musicalities, then that makes all the sense in the world :) The point is, I am going to write a sad song that sounds happy, and a happy song that sounds sad. Just to change things up a little :)