Ability to send quotes/price offers to a customer
Before you start working with someone they might want a price offer. The ability to send a price offer would be useful. This could be sent as a pdf attached to email. To make this happen you would need a basic product/service price registry. Then a Price offer/quote section where you select products and edit other terms of the offer.
Another neat way to do this would be to send a link to an online price offer instead of pdf. Then customer could review your offer online and accept it by clicking a "Accept this offer" button. After accepting you would then see in the offer list which offers have been accepted by customers.