Handy: A regex that validates all valid email addresses (give or take) - Axon Flux // A Ruby on Rails Blog

/^([\w!#$%&'*+-/=?^`{|}~]+.)*[\w!#$%&'*+-/=?^`{|}~]+@((((([a-z0-9]{1}[a-z0-9-]{0,62}[a-z0-9]{1})|[a-z]).)+[a-z]{2,6})|(\d{1,3}.){3}\d{1,3}(:\d{1,5})?)$/i

Lexy