Lucid_buttons is a project mainly written in Shell, it's free.
These are the lucid buttons to go with Ishimaro's pro lucid style for phpBB3: http://www.phpbb.com/customise/db/style/pro_ubuntu_lucid/
This work has been released into the public domain by the copyright holder. This applies worldwide. In case this is not legally possible: The copyright holder grants any entity the right to use this work for any purpose, without any conditions, unless such conditions are required by law.
convert.sh will re-create the .png images.