Actual secret lairs called "just add milk", because they are cereal box designs on cards. 3 cards for $29.99 1000 guesses on card designs, and I still never would've hit this. Unnecessary, Actual secret lairs called "just add milk", because they are cereal box designs on cards. 3 cards for $29.99 1000 guesses on card designs, and I still never would've hit this. Unnecessary, Business cards from recycled cereal boxes: idsgn (a design blog) New Cereal box Secret lair card and they are magically delicious Secret Lair: Just Add Milk! Just Add Milk Secret Lair