using php to write a checkbox value into a mysql database

Hey.... A short (and hopefully simple) question!! I'm trying to immeadiately write the value of a modified checkbox into a mysql table. Does anyoe know of a good/fast/easy way to accomplish this kind of task. Basically, when the user selects a box, or deselects the box, I'd like to be able to write the result to the mysql table. I'd like to be able to do this without having to use a submit button. Thanks for whatever assistance you can provide. Thanks.... Bruce bedouglas@earthlink.net