Different shipping labels on one website, anyone knows?

Does anyone know a website where you can purchase and print both shipping labels for different shipping providers? We ship orders using FedEx, UPS, USPS and DHL. Currently we have to log in to each website to create shipping labels and we're looking for one website that provides shipping service to different shipping providers. Any help would be greatly appreciated!

Does a website like this exist???

I think I might start one! Might be a chance to make some money. It sure would be convient if you could purchase different shipping labels all from one website. No more jumping from UPS, to FedEx, to DHL, etc...

I'm surprised no one else has thought of this.