Now Shipping! – The EyeLink 3; combined head and eye tracking at up to 1000 Hz.

FAQ: If using analog output, is the digital data also available over the ethernet link?
#1
Yes, you can use both data streams at the same time.

The digital data (sent over the Ethernet link to the Display PC) and the analog data (sent via the optional Analog card) are completely independent of each other. You can receive digital data for a gaze-contingent task while simultaneously recording the analog output on a separate device without any conflict or interference.