Cell phone hard drives

Ever seen those little USB hard drives? Like the key chain size ones that store 10-50 MB's of data on flash memory chips that you can move around from PC to PC? What I am proposing is for some enterprising cell phone manufacture to put one of those inside a cell phone, it wouldn't make the cell phone any bigger than they all ready are. There would be a USB port on the side of the phone to connect your PC to it. A drive would appear inside of "my computer" then you could drag your files to the cell phone and take them on your merry way, say from the home to the office. Now, taking this idea one step further. If a buddy of yours has the same phone, or one based around the same technology, you could call him up and say, "hey man, you gotta hear this MP3, I'll beam it to you." You would use the menus on the phone to select the file from the hard drive and send it to the person on the other end of the line. To make this work someone would have to do some programming and mucking around in cell phone software, maybe it would require the creation of a whole new transfer protocol specifically for cellular networks, but I'm sure it's possible. And with digital service it's likely that the architecture all ready exists to support these kinds of services.