How can I suppress the parameters from displaying in the URL? For instance, if I pass in a password, I don't want it to show up in the address bar.
Note there's no way to suppress parameters when using GET; that's the way the parameters are passed - as part of the URL, which the browser displays.
Oh, may be there is a way... Use a REDIRECT to tell the browser to fetch another page (you'll have to "remember" the parameters from the first request though!).