Rails - Jul 2006 - how to render/send an incoming stream of data?

Let''s say I want to proxy a data stream through rails.  I am
retrieving the data using HTTPResponse#read_body with a block.  This
block gets chunks of the stream as it''s read off the socket.  How do I
render/send this data to the end user without storing the whole file
in memory or disk?

thanks,
Tim