We've gotten some pretty catchy and surprisingly well-done mashups lately, namely the Ozzy plus Earth, Wind & Fire one, though this one gives it a run for its money. Once matched up in terms of key and tempo, Iron Maiden's "The Trooper" and Michael Jackson's "Beat It" work really, really well as one song!
Seriously, Iron Maiden's dual guitar action plus Eddie Van Halen's fretwork makes for a mashup of licks that's just undeniably catchy as hell.
[youtube]https://www.youtube.com/watch?v=dU2Pbm9wtnw[/youtube]
