I recently discovered some little-known ways to use your Gmail address that can give you greater control over your inbox and save you some time and headache. When you choose a Gmail address, you actually get more than just "firstname.lastname@example.org." Here are two different ways you can modify your Gmail address and still get your mail:
- Append a plus ("+") sign and any combination of words or numbers after your email address. For example, if your name was email@example.com, you could send mail to firstname.lastname@example.org or email@example.com.
- Insert one or several dots (".") anywhere in your email address. Gmail doesn't recognize periods as characters in addresses -- we just ignore them. For example, you could tell people your address was firstname.lastname@example.org, email@example.com or firstname.lastname@example.org. (We understand that there has been some confusion about this in the past, but to settle it once and for all, you can indeed receive mail at all the variations with dots.)
(Source from http://gmailblog.blogspot.com/2008/03/2-hidden-ways-to-get-more-from-your.html)