Following on from the great work of Tomaz Solc (here), I've produced some versions of his icons which we can distribute with gEDA under the GPL2 license. (Thanks to Tomaz's permission for the use of his work).
These new icons are based on the text-x-generic icon from the GNOME icon theme, which is licensed under the GPL2 license.
Tomaz's Tango icons are based on the text-x-generic icon from the Tango theme, which is licensed under the CC-BY-SA license.
We unfortunately can't ship Tomaz's CC-BY-SA licensed icons as part of gEDA due to licensing concerns, although they may be distributed separately as an addition to the Tango icon theme.
Look here and here to see what a project directory might look like in your file browser.
gEDA Schematic: application/x-geda-schematic
gEDA Symbol: application/x-geda-symbol
gEDA gsch2pcb project: application/x-geda-gsch2pcb-project
PCB layout: application/x-pcb-layout
PCB footprint: application/x-pcb-footprint
PCB netlist: application/x-pcb-netlist
Gerber file: application/x-gerber
Excellon file (ideas): application/x-excellon
gEDA Schematic (old portrait version)
gEDA Symbol (old portrait version)
gEDA gsch2pcb project (PCB on top for all sizes)
gEDA gsch2pcb project (early concepts)
PCB footprint (early versions)