I think my vote would be either chocolate or second-hand books, depending - there are plenty of places here where the equivalent of 2.39 sterling, which is pretty close to $5 Canadian, would get you two or three used paperbacks, but I'm out of experience with second-hand bookshops that side of the pond recently.

Alternatively, you could probably get three or four pieces of sushi for it, and eel would definitely count up there in the "most fun for your money" stakes.

[ Yay excuse for userpic that does not get used very often. ]

I also find myself reminded of the "fifty pence and a bunch of grapes" bit from Adrian Mole.