Use simple e-mailing aliasing to speed up your work flow while testing user registrations.
GMail Aliases for Testing Multiple Drupal User Registrations was a recent article I read that change my work flow with testing Drupal user registration. E-mail Aliasing as defined by Gmail: Using an address alias.
I use a slightly different technique than the one in the mentioned articles. Both technique can be used with any CMS including Wordpress and Joomla.
I found this more simple and it actually get through other site sign-ups more often than the other techniques. Most sites accept the dot or period, but not the plus sign (+). This process is also not exclusive to G-mail as many other e-mail systems use the e-mail aliasing as well.
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