Idea A towel, as has been stated before, is the single most important article a hitchhiker can carry. They are relatively inexpensive, portable, and rarely blow up unexpectedly.
Life is good.
You feel like the hoopiest frood to ever slap steel with a face-flannel. You reach for your trusty towel to wipe the warm blue sea foam from your brow, and you can't find it. There's nothing else to do, really, and here's why. Since the very reason for knowing where your towel is involves the supposition that if you can actually keep track of your towel no matter what then you must have the situation, whatever the situation may be, under control, it is only logical to assume that if you can't find your towel things are going very, very badly for you. You are either already, or about to become, one very unhoopy frood.