How about some common items we only THINK we know what they're for. Examples?
--That tiny pocket in our jeans is NOT for coins. It originated as extra protection for our pocket watches.
--The holes in our pot handles weren't planned for us to hang the pots, but rather to insert the spoon to keep it handy and not dripping on the stove.
--The drawer under the stove isn't for storing pots and pans (where else am I supposed to put them?) but as a warming oven for those who have gas stoves.
--Finally, those little tabs on the end of the rolls of foil and plastic wrap (which you never noticed until this minute) are designed to push in to stop the roll from flopping all over.

And how about some bids we may/may not be using properly? Today we're looking at rebids after pard responds No-trump.