Frusted is a scalp condition which occurs when someone tips the crumbs in the bottom of a cereal packet over one's head.
It was a popular sport in some boarding schools in the '50's apparently, and gave rise to the invention of a whole new genre of sugar coated cereals, which, after a dose of frustation would cause the crumby bits to mix with the hair dressing of the victim to form a rather sticky mess.
The absolute best type of cereal for this purpose was a coated corn flake, which became so popular that it's name was actually changed in a cynical marketing ploy to "Sugar Frusties".
Cheers,
P (and if you wait a minute or two, you'll be able to check the bonefides of this on Wikipedia!

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