call <this file's URL>?<URL of file to
list>[&<URL2>[&<URL3>[…]]]
the file to list must usually be on the same server as this file (depending
on the browser’s security settings)
the browser must support HTTPRequest or a substitute for it (Mozilla/Firefox
and Internet Explorer 5–7 are known to work; Opera 7.54 doesn’t, Opera 8
theoretically should but is full of bugs and usually doesn’t.)