Help!

1. To pay a flat fee is to pay one price for a number of things that can be purchased separately. So someone might pay a flat fee of $1000 for a vacation including rooms, meals and transportation.

Could you think of another example of the use of "flat" with the same meaning?

I have heard the term "flat rate" used for electricity charges. When the rate per unit is fixed irrespective of the number of units consumed they call it a "flat rate", as against the one when rate per unit consumed varies (usually increasing after every 100 or so units).