I have a Toshiba 6100 Laptop with only 2 USB Ports in the back. I am running a usb mouse and a usb Ipod, and I am in need to buy a external hardrive. Is there any portable external hard drive thats usb that I might be able to daisy chain to the computer. I thought I can use one usb port for the external drive and daisy chain the ipod to the external drive. Anybody knows who would make something like this?