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+== NAT Hole Punching Example ==
+
+This code should never be used, ever. But, it's a nice demonstration of how
+to punch holes and have two NAT'd peers talk to each other.
+
+Compile with:
+    $ gcc nat-punch-client.c -o client -lresolv
+    $ gcc nat-punch-server.c -o server
+
+
+Server is 1.2.3.4 and is on the public internet accepting UDP:49918.
+Client A is NAT'd and doesnt't know its IP address.
+Client B is NAT'd and doesnt't know its IP address.
+
+
+Server runs:
+   $ ./server
+
+Client A runs:
+   # ip link add wg0 type wireguard
+   # ip addr add 10.200.200.1 peer 10.200.200.2 dev wg0
+   # wg set wg0 private-key ... peer ... allowed-ips 10.200.200.2/32
+   # ./client 1.2.3.4 wg0
+   # ping 10.200.200.2
+
+Client B runs:
+   # ip link add wg0 type wireguard
+   # ip addr add 10.200.200.2 peer 10.200.200.1 dev wg0
+   # wg set wg0 private-key ... peer ... allowed-ips 10.200.200.1/32
+   # ./client 1.2.3.4 wg0
+   # ping 10.200.200.1
+
+And voila! Client A and Client B can speak from behind NAT.
+
+
+
+-----
+Keep in mind that this is proof-of-concept example code. It is not code that
+should be used in production, ever. It is woefully insecure, and is unsuitable
+for any real usage. With that said, this is useful as a learning example of
+how NAT hole punching might work within a more developed solution.