MogileFS is written in Perl and has been around for awhile:
http://www.danga.com/mogilefs/
http://www.capoune.net/mogilefs/
http://php-webdav.pureftpd.org/project/php-webdav
http://www.onlamp.com/pub/a/php/2000/09/15/php_mysql.html
This looks great:
http://forge.mysql.com/wiki/BLOB_Streaming_For_PHP
http://www.blobstreaming.org/index.php