Theirs:
http://sourceforge.net/projects/portabletor/files/ - 0.2.0.34
Ours:
http://www.portablefreeware.com/index.php?id=1088 - 0.2.0
Hope that people run this program with the "relay traffic" functions enabled. Your ISP won't like you very much, but people in oppressive regimes (such as Iran) are able to surf the internet without censorship.