Rent a Dress: You read that right! Websites like Rent the Runway offer designer dresses for a low price. You can rent a dress for either four or eight days, wear it on prom night, and send it back. You don't even have to worry about dry-cleaning the dress! The package will even come with a pre-paid and pre-addressed envelope so all you have to do is pack it and drop it on your mailbox. Worried that the dress won't fit you? Rent the Runway will send you the same dress in two different sizes at no additional cost.