I would highly recommend you to use SpamGourmet.com to help you create disposable email address on the fly, personally I have been using this system fot the past 5 months and throughly enjoy its features.
Give out self-destructing disposable email addresses whenever you want. The disposable addresses is in the form of someword.x.user@spamgourmet.com
where ‘someword’ is a word you have never used before, ‘x’ is the number of email messages you want to recieve from this email address, after that everything else is in the trash