I cross-compiled it, here is a static rtmpdump:
http://www.mediafire.com/?aq21y3blzd41by7
I included a build of librtmp.dll just in case someone wants it, but the main executable static x86 (not 64-bit, I have no idea how to cross-compile for that, but it shouldn't matter).
I also added a new command line option --mfc. It works like this:
rtmpdump --mfc video275:107735752:?:5286689 -o hellohollie.flv
or:
rtmpdump --mfc video489:107735752:?:7366515:1 -o tatertot.mp4
Basically the format is:
--mfc videoserver:sessionid:authentication:modelid:[hd]
Where authentication is a single '?' without quotes if guest. The 'hd' parameter is optional and setting it to 1 will attempt to latch onto the MP4 f4v path. The default is FLV.
This should be pretty self-explanatory, if you have no idea what sessionid is or how to get the video server you need to investigate MFC a bit more =] I provide no support or anything like that nor do I actually cap myself. Please note that you will need a socket connection to the chatserver or you'll get RickRolled. You can close it once you have the stream.
E.