The gccgo front end for gcc (also part of the gcc-4.7 release):
http://golang.org/doc/install/gccgo
It is a long page, but worth reading from top to bottom before building.
Which is referenced on this page:
http://code.google.com/p/go/
For those running Ubuntu (and probably Debian):
sudo apt-get install gccgo
Which means it might be worth checking packages.debian.org for an armel binary.