Mint.com is a family finance management service. It allows you to pull your financial information and bank transaction directly from the bank account. It allows user to add multiple accounts like checking, savings, credit card, retail cards etc. So it knows all your transaction data and your spending habits. 
Mint.com does a good job of estimating your budget and predicting spendings. Now, with a new feature, it also predicts when your bills are due. It notifies me when my credit cards bills, phone bills, utility bills are due. This puts Mint.com in a very unique position to make experience easy for its users. 
Since it already knows users’ payment details and it knows when the bills are due, they can put in a functionality to pay the bills in one click. Look at it as a One-Click-Bill-Payment system just like Amazon’s One-Click-Buy. 
There is only one missing link. They need to have registered vendor on their site. So for example, I am a bank of america customer and pay credit card bill every month. It already notifies me when the bill is due. Instead of just notifying, it can display a small button just beside the notification allowing me to pay the bill then and there. 
On BofA’s part, they need register themself as a vendor on mint.com and allow mint.com to initiate the transaction. Once this is done, all I as user have to do is click that “Pay” button and select the souce account from which I want to pay. And the payment is done on time, with ease. 
Also, to expand this feature further, mint.com can register vendors like T-Mobile and AT&T to pull in cell phone bills using account number and name verification. And bills can be paid from within mint.com. 
 
This makes mint.com a one-stop bill payment system for any vendor that wants to use this. What do you think? Would you use this as your bill payment system? do you know any other service that allows a similar feature?