Post but not Post

Hello. we all know that we can send variables to another PHP file via <form> tag and with post method. now i wonder if i can send variables from a script to another like POST method but not using form tags. like my question is how can i transfer data from form to form like the POST of the <form> tag, but w/o session variables or cookies, or url parameters (like the GET method), and w/o forms ofcourse? Currently, i'm doing this via hidden forms and automatic posting via JavaScript, but is there is any clean and better way? Thanks.