Cows naturally tend to face magnetic north. In a cowgapped system, you can achieve data exfiltration by placing large, powerful electromagnets outside of the pastures and turning it on and waiting for the cows to face the magnet for 1 and turning it off and waiting for the cows to face north for 0, with of course a second electromagnet in a different direction as a delimiter. With this method, one could steal proprietary cow info at a rate of 1 bit every 5 minutes.