I found these last month while in Melbourne, but forgot to mention them, because they are highly recommended.
Cadbury Egg n Spoon.
They came in three varieties - white, chocolate and dark.
They are done up like little egg cartons, with four chocolate eggs and 2 spoons in each one.
Inside each egg is a fluffy, whipped, mouse filling, so you end up eating it like a boiled egg... except you eat the shell as well.
It was a pity that there were four to a pack, so I only tried the white and the chocolate ones. I didn't try the dark variety. The white one was definitely the better one though, as it made the flavour more interesting. The regular (double) chocolate one was boring, being all chocolate.
I think they were about $10 each though, so not cheap.