The source code for Toucan, 7-Zip & CCrypt are available from the Toucan homepage:
http://portableapps.com/Toucan

All of the small icons apart from the 'Add Variable' icon (which is a mash-up of two of the other icons) are from the Oxygen icon set which is licensed under the GNU LGPL.

The large icons are copyright Neorame and in the app directory