Basic Broadcaster (bb) allows you to transfer text messages simply from one computer to another on a LAN. The messages are broadcast in the LAN and and can be received by each machine running bb. No setup is required other than starting the application. The messages are transmitted as plain text, and no encryption is done. The broadcasts can only be sent to machines on the same subnet as the sending machine, and will not be forwarded by routers to the Internet.
EARL is an HTTP tunneling proxy. It uses the POST method to transfer data. Since its datagrams are serialized objects, the traffic overhead is rather large. The datagrams are encrypted using AES to provide privacy and obfuscation to proxy maintainers. Inbound and outbound connections are possible. It is recommended to combine it with SOCKS proxies for a comfortable setup.