I am just dazzled by this.
Star Wars: an a capella tribute to John Williams
The video is actually lip-synching done by Corey Vidal to a tune by a strange Canadian group (I find myself saying those two words together an awful lot, you know) called Moosebutter. Corey's lyp-synching adds a great deal to this. Once you've listened, you may want to take a look at the lyrics.