flvstreamer is an open source command-line RTMP client intended
to stream audio or video content from all types of flash or rtmp
servers. Forked from rtmpdump v1.6 with encrypted rtmp and swf
verification support removed.

This tool provides free interoperability with the previously
undocumented adobe RTMP protocol so widely in use on the internet
today. It was developed entirely by reverse engineering methods and
without access to any proprietary or restrictive-license protocol
specifications.