Google Code-in

Cdec has a great program for creating word alignments called fast_align.

http://wiki.apertium.org/wiki/Alining_a_corpus_with_fast_align

It also has a program (atool) that will calculate symmetrised alignments:

http://www.cdec-decoder.org/guide/fast_align.html

Unfortunately you have to download all of cdec. The objective of this task is to take the atool program and make it a standalone app.