As a part of the [wiki:SummerOfCode Google Summer of Code 2007], Elias Pipping has been working on 
[http://elias.svn.binera.de/bin/cgi/viewvc.cgi/merge.rb?view=markup merge.rb], a script designed to merge multiple single-architecture trees into one universal tree.

for detailed information, see
 * its [http://elias.svn.binera.de subversion repository]
 * its [http://elias.binera.de/dokuwiki wiki]