It is possible to display a custom logo (up to 192 px width, 64 px height) in PeaZip file manager’s toolbar, replacing fm-theme.bmp in theme’s folder with a custom graphic file in BMP format.

FireCrystal theme contains icons form, or derived from:

Crystal and CristalClear icons

Original reference: http://www.everaldo.com/crystal/
Original license: LGPL

Tango Desktop Project icons

Original reference: http://tango.freedesktop.org/Tango_Desktop_Project
Original license: Attribution-Share Alike 2.5 Generic http://creativecommons.org/licenses/by-sa/2.5/