Wow, a N900 combined with a SDR, for tx/rx a hacked $40 USB controlled radio can be added or substituted for the SDR and a hand made yaggi to grab the weak signal like this
http://talk.maemo.org/showthread.php?t=91182
and/or
http://www.elazary.com/index.php?opt...uv5r&Itemid=17
and
http://ve2zaz.net/Arrow_Ant/Arrow_Style_Ant.htm
and the doppler frequency shift is computed and adjusted by gpredict!
An ultra portable way to get a shot at talking to the astronauts during ham radio time on the space station or even just using the free amateur radio com-sats