At my last job we had a fine Lexmark printer that would allow FTP:

Ruby#~> ftp elroy.xxxx.xxx
Connected to elroy.xxxx.xxx
220 FTP server: Lexmark Optra N Laser Printer ready
Name (elroy.xxxx.xxx:root):
230 user root logged in
ftp> quit
221 Goodbye

And is still wide open to the internet because they never remember to set the root password after the kung-fu reset wipes the prom.

Aside from that in no way does having FTP help you unless you have already prepared your "document" for printing with either "epson", "postscript", "wingraphics", or "lexmarkian" formats. (actually I think some can do PDF too). Having a HTTP file-upload "CGI" in there would be pretty cool and in-fact some printers on the market allow HTTP configuration, testing, and job loading already. You just upload an already prepared print format and off you go! Sexy and fun and easily abused if people keep erasing the root password when they deep-reset the machine.

And what printer does authentication? One with a builtin print-spooler? Why couldn't the HTTPd and FTPd both use the same authentication set as the built-in print-spooler?

--
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honk() if $you->love(perl)