Who's selling your email address

It's CSI, email-style. Try this neat hack from the Hedir forums:

1 ] Instead of just entering username@gmail.com as your email, enter it as username+samplesitecom@gmail.com instead

2 ] When Gmail sees a "+" in an email address, it uses all the characters to the left of the plus sign to know who to send it to. In this example it would still send it to username@gmail.com.

3 ] If you search Gmail for username+samplesitecom, you will see all massages that were sent to that email address.

4 ] To see who is responsible for sending a specific message click the Show Details link and you will see the complete address.

You can also avoid registrations all together with BugMeNot.
Or try 2Prong: World's simplest disposable e-mail

Source : Lifehacker

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Stay secure with Gmail

Most people that use Gmail sign in by going to gmail.com.

When you sign in there your authentication is perfectly secure because you’re using Google’s SSL certificate. However, once signed in, you’re on your own! There is nothing stopping random people from sniffing your traffic and getting your banking information and social security number.

Try signing in use the following link: https://mail.google.com.
This will keep your information encrypted after you authenticate.