Q: how did you do the thing in "hello sexy pants" where there was that one spoken line that only comes out of one side of my headphones?
A: that's called 'pan.' it's available in every music making software or hardware ever, as long as you are listening to it in stereo. 'pan' is how far left or right the sound is. actually most music in stereo has all the parts positioned in slightly different places, not just exactly center. occasionally for special effects it is fun to throw something all the way to one side