Talk about a collision.
I use "mash-ups" to teach synthesis to my composition students. Usually, I just bring in an audio clip mash-up that is one song combined with another. But, yesterday I found this interesting video. Someone mashed SIX fairly popular songs and videos together. I was thoroughly impressed. The combination of the first and second song is genius, in my opinion. Trust me, you want to watch this.
(by the way, visit Mashuptown.com