@Robin L's gift list above reminds me of a (reputed) classified ad from days of yore.
EDIT: And speaking of tapeworms... I once read that at least one "diet pill" of the pre-Harrison Drug Act, Snakeoil days of pharmacy, contained tapeworm eggs. Pretty much guaranteed to work, I suppose.
Oh, and speaking of
snakeoil... the redoubtable Wyeth pharmaceutical company (gobbled up by Pfizer in 2009*) got its start, quite literally, selling snake oil (or snake-oil-esque) products in the 19th century. Oh, and the drug lord Wyeths were relatives of the artist Wyeths. But I digress...
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* don't ask me why I know this.