Regarding the idea for a mosaic effect font in the thread at TypeCon2005 in the Specification forum, the Galileo Lettering Mosaic font is now available at the Fonts designed by William Overington webpage.
A three page support document, mosaic.PDF, is available both from that page and directly from this link.
http://www.users.globalnet.co.uk/~ngo/mosaic.PDF
William