Here's a really lame home page for ppmtofb, a useful little package for Linux that lets you display graphics on framebuffer consoles. The following framebuffer organizations are currently supported in color and grayscale modes:
As far as I know, this covers all of the available framebuffer organizations as of Linux 2.4.
Since you probably have things other than ppm files you want to display, the program includes a frontend called fbview that handles conversions from all sorts of useful formats and can scale pictures to your display size. See its man page for all of its capabilities.
If you use the Debian distribution, you can download and install the latest ppmtofb package from the unstable tree of your favorite Debian mirror. (See the ppmtofb package page for details.)
Users of other distributions should download and compile the source package, and possibly package it for their own distribution.
Probably 0.29, but check the source link to make sure! Read the changelog for details of changes between versions.
You can also consult the Freshmeat II appindex record for ppmtofb.
Geert Uytterhoeven wrote the original version, ppmtoagafb, as a proof-of-concept for the framebuffer interface. I (Chris Lawrence) took over the code, added all sorts of bloat, and generally have made such a mess of things that Geert is probably sorry his name's in the code. ;-).
Portions are derived from ppmtoilbm from the NetPBM project, an Amiga HAM8 picture displayer by Günther Rörich, and Ben Pfaff's bogl library (from which the VGA16 support was pilfered). Robert de Bath contributed numerous suggestions that improved the cfb support significantly.
ppmtofb is free software licensed under the GNU General Public License.