Muggles' Guide to Harry Potter/Characters/Eddie Carmichael

Overview
Eddie Carmichael is a Ravenclaw student one year older than Harry.

Order of the Phoenix
As OWL exams approach, many students are trying to earn some easy money from selling items touted as being able to give some advantage in the exams. These substances are against the rules at Hogwarts, and are often actually dangerous drugs – one student was offering "powdered dragon claw" for sale, which on inspection turned out to be dried doxy droppings. Eddie offers Baruffio's Brain Elixir, a supposed brain stimulant. Harry and Ron were just about to buy some from him when Hermione (acting as a prefect) confiscates all of it and pours it down the toilet.

Analysis
We have no idea what Baruffio's Brain Elixir may be, but it is almost certainly ineffective, probably water with some magical herbs mixed in at random to give it some sort of color and flavour to justify the price (12 Galleons a pint) Eddie is asking. A reader with a good memory may recognize the name, though, as in Harry's first year, Professor Flitwick had cautioned his Charms class to "never forget Wizard Baruffio, who said 's' instead of 'f' and found himself on the floor with a buffalo on his chest."