Email Confirmation Link

Hello,

I need to create a simple email address verification system, as you see on many websites when you create a new account.

I want to send out an email to a user which will authenticate their email address. The email would contain a link, which when clicked, would toggle a field in our database confirming that the user has clicked the link and is using a valid email account.

For example, a new user signs up and enters their email address in a form. The user then receives an email saying, "Thank you for joining, please click this link to confirm your account." The user then clicks the link, which changes a field in our database. This lets us know that the email address is valid, and the user is responsive.

Any help you can offer in creating this system would be much appreciated!

Cheers!
Austin