have a flickr account? you can create mosaics with your own or others' pics (if they allow sharing) with mosaic maker from bighugelabs.com. i was just foolin' around and this isn't the best composition, but it's a rockin' tool. try it! you can adjust background color, space between squares (pics should look good in square format), adjust number of rows and columns, etc. like i said, rockin' - and free!