The Irrlicht FIGDriver is a superfont (metafont?), that is an IGUIFont which is composed of other IGUIFonts. It allows the user to load FIGlet fonts from JavE, the ASCII equivalent of Photoshop:

To load a font you simply do something like this:

// First use the Irrlicht font tool to generate a fixed-width font,
// use the one provided, or the Console device's built-in font.

IGUIFont* font = guienv->getFont("fixed.xml");

// create an instance of a figlet font
CGUIFIGletFont* figFont = new CGUIFIGletFont(font);

// open a FIGlet file for reading
io::IReadFile* file 
  = device->getFileSystem()->createAndOpenFile("figlets/big.flf");
// load the font data

// set the font to the skin's default font

// remember to drop the things you created!


// all done!

You can get the code from SVN, also check out the docs.