Well, I don't really have one right now, but a couple days ago I had Step Up by Drowning Pool, and Re-Align by Godsmack stuck in my head at the same time. When one ran it's course, the other took over, then when that one was done, the other took over. And so on. . .
Linkin Park:[Points of Authority] Forfeit the game/Before somebody else Takes you out of the frame/Puts your name to shame
Nirvana, Smells like teen spirit (I was listening a special thing on M+ about Kurt Cobain so don't be surprised)