The Hitchhiker's Guide to the Galaxy: You're so unhip, its a wonder your bums don't fall off

The one liner that really tickled me recently, from my new favourite book - The Hitchhiker's Guide to the Galaxy..read it NOW if you haven't already
"You're so unhip, its a wonder your bums don't fall off"
(I've been using this on my sister a lot lately, with hilarious results i might add)