@ashflower: After I listened the "Stayin' Alive In the Wall" mashup , I had a very similar reaction. Whenever I'm listening either of the songs now, I keep thinking of the mashup and wish I was listening to it, haha.
Every time I hear the intro to Hallowed Be Thy Name and Sad But True, I automatically think of these mashups and actually wish I was listening to them instead! You sir, are a genius. And Maiden Goes To Hollywood is better than the original Rime of the Ancient Mariner song that Maiden did. No joke.