Elvis & Celine Dion in "American Idol - Idol Gives Back" segment

I saw this portion of "American Idol - Idol Gives Back" last night while I was flipping channels. I know there's some behind-the-scenes CGI technology and camera tricks regarding this, but I thought to myself that it's great television magic with Celine Dion singing alongside "The King," Elvis Presley with the song,"If I Can Dream." I found it cool. Hope you will, too.