Filling/saving internet forms, and importing data later

I sometimes (today/tomorrow) need to fill some internet forms (html/css - not pdf), and to either save them for submitting later, or to send them to someone else to submit. One option would be print them as pdf, but it would be easier if I could save the forms in such a way that I, or another person, could later import the data directly back into blank versions of these forms in an open browser.

Anyone know how?

(I use Firefox, but also have IE).