Numeric Form Posting

I need a java script form that will post a consecutive number to the form confirmation page.

For example, if I submit the form, I will the confirmation page to read:

JGH10031416

The next user that submits the form I would need the number to read:

JGH10031417

and so on....18, 19, 20, 21, 22, 23, 24, etc.

This code would be used to generate unique ID's for a membership card.

you will need some sort of server-parsed scripting to either communicate with a database or a text file that stores what the last # was generated so it can increase the number by 1. javascript cannot know what another's browser has loaded for a number, so it would output the same exact number as someone else, no doubt.