I've crafted a little diagram to help with my question, which is does a device like this exist? I currently run an older MacBook Pro + 23'' Apple Cinema HD. As most of you probably know, the Cinema HD has a 2-port USB & 2-port FW400 hub in the back of the display. I plan on buying the new 27'' iMac, and I plan on hooking up the 23'' Cinema. I know I can simply buy Apple's Mini-DP to DVI adapter to make this happen, along with a thunderbolt to USB/Firewire hub, but I'd love to be able to use one adapter/device (and one Thunderbolt port) to plug in the Cinema Display's DVI, USB, and Firewire cables to the new iMac. I've searched around and haven't found such a device, so I'm doubtful one exists, but I thought I'd post here anyway. Seems like there'd be a niche market for owners of Thunderbolt Macs who also own and continue to use Apple's DVI Displays.