You can daisy-chain, PROVIDED the requisite adapters/devices in the chain support it. Not all Tunderbolt devices support daisy-chaining, therefore must be at the end of any "chain". None of the projected Sonnet products seem to support it either. So, unless that other device you plan to use supports it (the monitor), you are unable to use them simultaneously. I suppose it gives some comfort to Apple on the pricing of their Tunderbolt Display.