"Song 8" is an unreleased instrumental, that Beck gave to the filmmakers of I Am Number Four
. They included a snippet of "Curfew" in the film. In 2017, both songs were leaked out.
I have never been a big fan of Beck's instrumentals. There's not a lot, but I usually just tolerate them. This one, I like though. It's got Beck's electric guitar shredding which is fun and a little dark, but the beat behind it is catchy, lighter. Interesting mix of things.