Other form submission targets

ftp:

GETs the specified file (not very useful)

data:

Load the specified URI, possibly after substituting in the form input

file:

Retrieve the file (GET), launch the file and pass the form input to it (POST), store the form input in the file (PUT), or delete the named file (DELETE)

mailto:

Form input becomes mail headers, except for POST where it's the message body

javascript:

Ignore form input; load the URI